#include "postgres.h"
#include <time.h>
#include "access/nbtree.h"
#include "access/reloptions.h"
#include "access/relscan.h"
#include "catalog/catalog.h"
#include "commands/progress.h"
#include "lib/qunique.h"
#include "miscadmin.h"
#include "utils/array.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"

Include dependency graph for nbtutils.c:

Data Structures
struct	BTSortArrayContext

struct	BTOneVacInfo

struct	BTVacInfo

Typedefs
typedef struct BTSortArrayContext	BTSortArrayContext

typedef struct BTOneVacInfo	BTOneVacInfo

typedef struct BTVacInfo	BTVacInfo

Functions
static Datum	_bt_find_extreme_element (IndexScanDesc scan, ScanKey skey, StrategyNumber strat, Datum *elems, int nelems)

static int	_bt_sort_array_elements (IndexScanDesc scan, ScanKey skey, bool reverse, Datum *elems, int nelems)

static int	_bt_compare_array_elements (const void a, const void b, void *arg)

static bool	_bt_compare_scankey_args (IndexScanDesc scan, ScanKey op, ScanKey leftarg, ScanKey rightarg, bool *result)

static bool	_bt_fix_scankey_strategy (ScanKey skey, int16 *indoption)

static void	_bt_mark_scankey_required (ScanKey skey)

static bool	_bt_check_rowcompare (ScanKey skey, IndexTuple tuple, int tupnatts, TupleDesc tupdesc, ScanDirection dir, bool *continuescan)

static int	_bt_keep_natts (Relation rel, IndexTuple lastleft, IndexTuple firstright, BTScanInsert itup_key)

BTScanInsert	_bt_mkscankey (Relation rel, IndexTuple itup)

void	_bt_freestack (BTStack stack)

void	_bt_preprocess_array_keys (IndexScanDesc scan)

void	_bt_start_array_keys (IndexScanDesc scan, ScanDirection dir)

bool	_bt_advance_array_keys (IndexScanDesc scan, ScanDirection dir)

void	_bt_mark_array_keys (IndexScanDesc scan)

void	_bt_restore_array_keys (IndexScanDesc scan)

void	_bt_preprocess_keys (IndexScanDesc scan)

bool	_bt_checkkeys (IndexScanDesc scan, IndexTuple tuple, int tupnatts, ScanDirection dir, bool *continuescan)

void	_bt_killitems (IndexScanDesc scan)

BTCycleId	_bt_vacuum_cycleid (Relation rel)

BTCycleId	_bt_start_vacuum (Relation rel)

void	_bt_end_vacuum (Relation rel)

void	_bt_end_vacuum_callback (int code, Datum arg)

Size	BTreeShmemSize (void)

void	BTreeShmemInit (void)

bytea *	btoptions (Datum reloptions, bool validate)

bool	btproperty (Oid index_oid, int attno, IndexAMProperty prop, const char propname, bool res, bool *isnull)

char *	btbuildphasename (int64 phasenum)

IndexTuple	_bt_truncate (Relation rel, IndexTuple lastleft, IndexTuple firstright, BTScanInsert itup_key)

int	_bt_keep_natts_fast (Relation rel, IndexTuple lastleft, IndexTuple firstright)

bool	_bt_check_natts (Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum)

void	_bt_check_third_page (Relation rel, Relation heap, bool needheaptidspace, Page page, IndexTuple newtup)

bool	_bt_allequalimage (Relation rel, bool debugmessage)

Variables
static BTVacInfo *	btvacinfo

Typedef Documentation

◆ BTOneVacInfo

typedef struct BTOneVacInfo BTOneVacInfo

◆ BTSortArrayContext

typedef struct BTSortArrayContext BTSortArrayContext

◆ BTVacInfo

typedef struct BTVacInfo BTVacInfo

Function Documentation

◆ _bt_advance_array_keys()

bool _bt_advance_array_keys	(	IndexScanDesc	scan,
		ScanDirection	dir
	)

Definition at line 551 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     bool        found = false;
     int         i;
  
     /*
      * We must advance the last array key most quickly, since it will
      * correspond to the lowest-order index column among the available
      * qualifications. This is necessary to ensure correct ordering of output
      * when there are multiple array keys.
      */
     for (i = so->numArrayKeys - 1; i >= 0; i--)
     {
         BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
         ScanKey     skey = &so->arrayKeyData[curArrayKey->scan_key];
         int         cur_elem = curArrayKey->cur_elem;
         int         num_elems = curArrayKey->num_elems;
  
         if (ScanDirectionIsBackward(dir))
         {
             if (--cur_elem < 0)
             {
                 cur_elem = num_elems - 1;
                 found = false;  /* need to advance next array key */
             }
             else
                 found = true;
         }
         else
         {
             if (++cur_elem >= num_elems)
             {
                 cur_elem = 0;
                 found = false;  /* need to advance next array key */
             }
             else
                 found = true;
         }
  
         curArrayKey->cur_elem = cur_elem;
         skey->sk_argument = curArrayKey->elem_values[cur_elem];
         if (found)
             break;
     }
  
     /* advance parallel scan */
     if (scan->parallel_scan != NULL)
         _bt_parallel_advance_array_keys(scan);
  
     return found;
 }

References _bt_parallel_advance_array_keys(), BTScanOpaqueData::arrayKeyData, BTScanOpaqueData::arrayKeys, BTArrayKeyInfo::cur_elem, BTArrayKeyInfo::elem_values, i, BTArrayKeyInfo::num_elems, BTScanOpaqueData::numArrayKeys, IndexScanDescData::opaque, IndexScanDescData::parallel_scan, BTArrayKeyInfo::scan_key, ScanDirectionIsBackward, and ScanKeyData::sk_argument.

Referenced by btgetbitmap(), and btgettuple().

◆ _bt_allequalimage()

bool _bt_allequalimage	(	Relation	rel,
		bool	debugmessage
	)

Definition at line 2696 of file nbtutils.c.

 {
     bool        allequalimage = true;
  
     /* INCLUDE indexes can never support deduplication */
     if (IndexRelationGetNumberOfAttributes(rel) !=
         IndexRelationGetNumberOfKeyAttributes(rel))
         return false;
  
     for (int i = 0; i < IndexRelationGetNumberOfKeyAttributes(rel); i++)
     {
         Oid         opfamily = rel->rd_opfamily[i];
         Oid         opcintype = rel->rd_opcintype[i];
         Oid         collation = rel->rd_indcollation[i];
         Oid         equalimageproc;
  
         equalimageproc = get_opfamily_proc(opfamily, opcintype, opcintype,
                                            BTEQUALIMAGE_PROC);
  
         /*
          * If there is no BTEQUALIMAGE_PROC then deduplication is assumed to
          * be unsafe.  Otherwise, actually call proc and see what it says.
          */
         if (!OidIsValid(equalimageproc) ||
             !DatumGetBool(OidFunctionCall1Coll(equalimageproc, collation,
                                                ObjectIdGetDatum(opcintype))))
         {
             allequalimage = false;
             break;
         }
     }
  
     if (debugmessage)
     {
         if (allequalimage)
             elog(DEBUG1, "index \"%s\" can safely use deduplication",
                  RelationGetRelationName(rel));
         else
             elog(DEBUG1, "index \"%s\" cannot use deduplication",
                  RelationGetRelationName(rel));
     }
  
     return allequalimage;
 }

References BTEQUALIMAGE_PROC, DatumGetBool(), DEBUG1, elog(), get_opfamily_proc(), i, IndexRelationGetNumberOfAttributes, IndexRelationGetNumberOfKeyAttributes, ObjectIdGetDatum(), OidFunctionCall1Coll(), OidIsValid, RelationData::rd_indcollation, RelationData::rd_opcintype, RelationData::rd_opfamily, and RelationGetRelationName.

Referenced by _bt_leafbuild(), bt_index_check_internal(), and btbuildempty().

◆ _bt_check_natts()

bool _bt_check_natts	(	Relation	rel,
		bool	heapkeyspace,
		Page	page,
		OffsetNumber	offnum
	)

Definition at line 2471 of file nbtutils.c.

 {
     int16       natts = IndexRelationGetNumberOfAttributes(rel);
     int16       nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
     BTPageOpaque opaque = BTPageGetOpaque(page);
     IndexTuple  itup;
     int         tupnatts;
  
     /*
      * We cannot reliably test a deleted or half-dead page, since they have
      * dummy high keys
      */
     if (P_IGNORE(opaque))
         return true;
  
     Assert(offnum >= FirstOffsetNumber &&
            offnum <= PageGetMaxOffsetNumber(page));
  
     /*
      * Mask allocated for number of keys in index tuple must be able to fit
      * maximum possible number of index attributes
      */
     StaticAssertStmt(BT_OFFSET_MASK >= INDEX_MAX_KEYS,
                      "BT_OFFSET_MASK can't fit INDEX_MAX_KEYS");
  
     itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, offnum));
     tupnatts = BTreeTupleGetNAtts(itup, rel);
  
     /* !heapkeyspace indexes do not support deduplication */
     if (!heapkeyspace && BTreeTupleIsPosting(itup))
         return false;
  
     /* Posting list tuples should never have "pivot heap TID" bit set */
     if (BTreeTupleIsPosting(itup) &&
         (ItemPointerGetOffsetNumberNoCheck(&itup->t_tid) &
          BT_PIVOT_HEAP_TID_ATTR) != 0)
         return false;
  
     /* INCLUDE indexes do not support deduplication */
     if (natts != nkeyatts && BTreeTupleIsPosting(itup))
         return false;
  
     if (P_ISLEAF(opaque))
     {
         if (offnum >= P_FIRSTDATAKEY(opaque))
         {
             /*
              * Non-pivot tuple should never be explicitly marked as a pivot
              * tuple
              */
             if (BTreeTupleIsPivot(itup))
                 return false;
  
             /*
              * Leaf tuples that are not the page high key (non-pivot tuples)
              * should never be truncated.  (Note that tupnatts must have been
              * inferred, even with a posting list tuple, because only pivot
              * tuples store tupnatts directly.)
              */
             return tupnatts == natts;
         }
         else
         {
             /*
              * Rightmost page doesn't contain a page high key, so tuple was
              * checked above as ordinary leaf tuple
              */
             Assert(!P_RIGHTMOST(opaque));
  
             /*
              * !heapkeyspace high key tuple contains only key attributes. Note
              * that tupnatts will only have been explicitly represented in
              * !heapkeyspace indexes that happen to have non-key attributes.
              */
             if (!heapkeyspace)
                 return tupnatts == nkeyatts;
  
             /* Use generic heapkeyspace pivot tuple handling */
         }
     }
     else                        /* !P_ISLEAF(opaque) */
     {
         if (offnum == P_FIRSTDATAKEY(opaque))
         {
             /*
              * The first tuple on any internal page (possibly the first after
              * its high key) is its negative infinity tuple.  Negative
              * infinity tuples are always truncated to zero attributes.  They
              * are a particular kind of pivot tuple.
              */
             if (heapkeyspace)
                 return tupnatts == 0;
  
             /*
              * The number of attributes won't be explicitly represented if the
              * negative infinity tuple was generated during a page split that
              * occurred with a version of Postgres before v11.  There must be
              * a problem when there is an explicit representation that is
              * non-zero, or when there is no explicit representation and the
              * tuple is evidently not a pre-pg_upgrade tuple.
              *
              * Prior to v11, downlinks always had P_HIKEY as their offset.
              * Accept that as an alternative indication of a valid
              * !heapkeyspace negative infinity tuple.
              */
             return tupnatts == 0 ||
                 ItemPointerGetOffsetNumber(&(itup->t_tid)) == P_HIKEY;
         }
         else
         {
             /*
              * !heapkeyspace downlink tuple with separator key contains only
              * key attributes.  Note that tupnatts will only have been
              * explicitly represented in !heapkeyspace indexes that happen to
              * have non-key attributes.
              */
             if (!heapkeyspace)
                 return tupnatts == nkeyatts;
  
             /* Use generic heapkeyspace pivot tuple handling */
         }
     }
  
     /* Handle heapkeyspace pivot tuples (excluding minus infinity items) */
     Assert(heapkeyspace);
  
     /*
      * Explicit representation of the number of attributes is mandatory with
      * heapkeyspace index pivot tuples, regardless of whether or not there are
      * non-key attributes.
      */
     if (!BTreeTupleIsPivot(itup))
         return false;
  
     /* Pivot tuple should not use posting list representation (redundant) */
     if (BTreeTupleIsPosting(itup))
         return false;
  
     /*
      * Heap TID is a tiebreaker key attribute, so it cannot be untruncated
      * when any other key attribute is truncated
      */
     if (BTreeTupleGetHeapTID(itup) != NULL && tupnatts != nkeyatts)
         return false;
  
     /*
      * Pivot tuple must have at least one untruncated key attribute (minus
      * infinity pivot tuples are the only exception).  Pivot tuples can never
      * represent that there is a value present for a key attribute that
      * exceeds pg_index.indnkeyatts for the index.
      */
     return tupnatts > 0 && tupnatts <= nkeyatts;
 }

References Assert(), BT_OFFSET_MASK, BT_PIVOT_HEAP_TID_ATTR, BTPageGetOpaque, BTreeTupleGetHeapTID(), BTreeTupleGetNAtts, BTreeTupleIsPivot(), BTreeTupleIsPosting(), FirstOffsetNumber, INDEX_MAX_KEYS, IndexRelationGetNumberOfAttributes, IndexRelationGetNumberOfKeyAttributes, ItemPointerGetOffsetNumber(), ItemPointerGetOffsetNumberNoCheck(), P_FIRSTDATAKEY, P_HIKEY, P_IGNORE, P_ISLEAF, P_RIGHTMOST, PageGetItem(), PageGetItemId(), PageGetMaxOffsetNumber(), StaticAssertStmt, and IndexTupleData::t_tid.

Referenced by _bt_compare(), and bt_target_page_check().

◆ _bt_check_rowcompare()

static bool _bt_check_rowcompare	(	ScanKey	skey,
		IndexTuple	tuple,
		int	tupnatts,
		TupleDesc	tupdesc,
		ScanDirection	dir,
		bool *	continuescan
	)

static

Definition at line 1529 of file nbtutils.c.

 {
     ScanKey     subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
     int32       cmpresult = 0;
     bool        result;
  
     /* First subkey should be same as the header says */
     Assert(subkey->sk_attno == skey->sk_attno);
  
     /* Loop over columns of the row condition */
     for (;;)
     {
         Datum       datum;
         bool        isNull;
  
         Assert(subkey->sk_flags & SK_ROW_MEMBER);
  
         if (subkey->sk_attno > tupnatts)
         {
             /*
              * This attribute is truncated (must be high key).  The value for
              * this attribute in the first non-pivot tuple on the page to the
              * right could be any possible value.  Assume that truncated
              * attribute passes the qual.
              */
             Assert(ScanDirectionIsForward(dir));
             Assert(BTreeTupleIsPivot(tuple));
             cmpresult = 0;
             if (subkey->sk_flags & SK_ROW_END)
                 break;
             subkey++;
             continue;
         }
  
         datum = index_getattr(tuple,
                               subkey->sk_attno,
                               tupdesc,
                               &isNull);
  
         if (isNull)
         {
             if (subkey->sk_flags & SK_BT_NULLS_FIRST)
             {
                 /*
                  * Since NULLs are sorted before non-NULLs, we know we have
                  * reached the lower limit of the range of values for this
                  * index attr.  On a backward scan, we can stop if this qual
                  * is one of the "must match" subset.  We can stop regardless
                  * of whether the qual is > or <, so long as it's required,
                  * because it's not possible for any future tuples to pass. On
                  * a forward scan, however, we must keep going, because we may
                  * have initially positioned to the start of the index.
                  */
                 if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
                     ScanDirectionIsBackward(dir))
                     *continuescan = false;
             }
             else
             {
                 /*
                  * Since NULLs are sorted after non-NULLs, we know we have
                  * reached the upper limit of the range of values for this
                  * index attr.  On a forward scan, we can stop if this qual is
                  * one of the "must match" subset.  We can stop regardless of
                  * whether the qual is > or <, so long as it's required,
                  * because it's not possible for any future tuples to pass. On
                  * a backward scan, however, we must keep going, because we
                  * may have initially positioned to the end of the index.
                  */
                 if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
                     ScanDirectionIsForward(dir))
                     *continuescan = false;
             }
  
             /*
              * In any case, this indextuple doesn't match the qual.
              */
             return false;
         }
  
         if (subkey->sk_flags & SK_ISNULL)
         {
             /*
              * Unlike the simple-scankey case, this isn't a disallowed case.
              * But it can never match.  If all the earlier row comparison
              * columns are required for the scan direction, we can stop the
              * scan, because there can't be another tuple that will succeed.
              */
             if (subkey != (ScanKey) DatumGetPointer(skey->sk_argument))
                 subkey--;
             if ((subkey->sk_flags & SK_BT_REQFWD) &&
                 ScanDirectionIsForward(dir))
                 *continuescan = false;
             else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
                      ScanDirectionIsBackward(dir))
                 *continuescan = false;
             return false;
         }
  
         /* Perform the test --- three-way comparison not bool operator */
         cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
                                                     subkey->sk_collation,
                                                     datum,
                                                     subkey->sk_argument));
  
         if (subkey->sk_flags & SK_BT_DESC)
             INVERT_COMPARE_RESULT(cmpresult);
  
         /* Done comparing if unequal, else advance to next column */
         if (cmpresult != 0)
             break;
  
         if (subkey->sk_flags & SK_ROW_END)
             break;
         subkey++;
     }
  
     /*
      * At this point cmpresult indicates the overall result of the row
      * comparison, and subkey points to the deciding column (or the last
      * column if the result is "=").
      */
     switch (subkey->sk_strategy)
     {
             /* EQ and NE cases aren't allowed here */
         case BTLessStrategyNumber:
             result = (cmpresult < 0);
             break;
         case BTLessEqualStrategyNumber:
             result = (cmpresult <= 0);
             break;
         case BTGreaterEqualStrategyNumber:
             result = (cmpresult >= 0);
             break;
         case BTGreaterStrategyNumber:
             result = (cmpresult > 0);
             break;
         default:
             elog(ERROR, "unrecognized RowCompareType: %d",
                  (int) subkey->sk_strategy);
             result = 0;         /* keep compiler quiet */
             break;
     }
  
     if (!result)
     {
         /*
          * Tuple fails this qual.  If it's a required qual for the current
          * scan direction, then we can conclude no further tuples will pass,
          * either.  Note we have to look at the deciding column, not
          * necessarily the first or last column of the row condition.
          */
         if ((subkey->sk_flags & SK_BT_REQFWD) &&
             ScanDirectionIsForward(dir))
             *continuescan = false;
         else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
                  ScanDirectionIsBackward(dir))
             *continuescan = false;
     }
  
     return result;
 }

References Assert(), BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, BTreeTupleIsPivot(), DatumGetInt32(), DatumGetPointer(), elog(), ERROR, FunctionCall2Coll(), index_getattr(), INVERT_COMPARE_RESULT, ScanDirectionIsBackward, ScanDirectionIsForward, ScanKeyData::sk_argument, ScanKeyData::sk_attno, SK_BT_DESC, SK_BT_NULLS_FIRST, SK_BT_REQBKWD, SK_BT_REQFWD, ScanKeyData::sk_collation, ScanKeyData::sk_flags, ScanKeyData::sk_func, SK_ISNULL, SK_ROW_END, SK_ROW_MEMBER, and ScanKeyData::sk_strategy.

Referenced by _bt_checkkeys().

◆ _bt_check_third_page()

void _bt_check_third_page	(	Relation	rel,
		Relation	heap,
		bool	needheaptidspace,
		Page	page,
		IndexTuple	newtup
	)

Definition at line 2638 of file nbtutils.c.

 {
     Size        itemsz;
     BTPageOpaque opaque;
  
     itemsz = MAXALIGN(IndexTupleSize(newtup));
  
     /* Double check item size against limit */
     if (itemsz <= BTMaxItemSize(page))
         return;
  
     /*
      * Tuple is probably too large to fit on page, but it's possible that the
      * index uses version 2 or version 3, or that page is an internal page, in
      * which case a slightly higher limit applies.
      */
     if (!needheaptidspace && itemsz <= BTMaxItemSizeNoHeapTid(page))
         return;
  
     /*
      * Internal page insertions cannot fail here, because that would mean that
      * an earlier leaf level insertion that should have failed didn't
      */
     opaque = BTPageGetOpaque(page);
     if (!P_ISLEAF(opaque))
         elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"",
              itemsz, RelationGetRelationName(rel));
  
     ereport(ERROR,
             (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
              errmsg("index row size %zu exceeds btree version %u maximum %zu for index \"%s\"",
                     itemsz,
                     needheaptidspace ? BTREE_VERSION : BTREE_NOVAC_VERSION,
                     needheaptidspace ? BTMaxItemSize(page) :
                     BTMaxItemSizeNoHeapTid(page),
                     RelationGetRelationName(rel)),
              errdetail("Index row references tuple (%u,%u) in relation \"%s\".",
                        ItemPointerGetBlockNumber(BTreeTupleGetHeapTID(newtup)),
                        ItemPointerGetOffsetNumber(BTreeTupleGetHeapTID(newtup)),
                        RelationGetRelationName(heap)),
              errhint("Values larger than 1/3 of a buffer page cannot be indexed.\n"
                      "Consider a function index of an MD5 hash of the value, "
                      "or use full text indexing."),
              errtableconstraint(heap, RelationGetRelationName(rel))));
 }

References BTMaxItemSize, BTMaxItemSizeNoHeapTid, BTPageGetOpaque, BTREE_NOVAC_VERSION, BTREE_VERSION, BTreeTupleGetHeapTID(), elog(), ereport, errcode(), errdetail(), errhint(), errmsg(), ERROR, errtableconstraint(), IndexTupleSize, ItemPointerGetBlockNumber(), ItemPointerGetOffsetNumber(), MAXALIGN, P_ISLEAF, and RelationGetRelationName.

Referenced by _bt_buildadd(), and _bt_findinsertloc().

◆ _bt_checkkeys()

bool _bt_checkkeys	(	IndexScanDesc	scan,
		IndexTuple	tuple,
		int	tupnatts,
		ScanDirection	dir,
		bool *	continuescan
	)

Definition at line 1362 of file nbtutils.c.

 {
     TupleDesc   tupdesc;
     BTScanOpaque so;
     int         keysz;
     int         ikey;
     ScanKey     key;
  
     Assert(BTreeTupleGetNAtts(tuple, scan->indexRelation) == tupnatts);
  
     *continuescan = true;       /* default assumption */
  
     tupdesc = RelationGetDescr(scan->indexRelation);
     so = (BTScanOpaque) scan->opaque;
     keysz = so->numberOfKeys;
  
     for (key = so->keyData, ikey = 0; ikey < keysz; key++, ikey++)
     {
         Datum       datum;
         bool        isNull;
         Datum       test;
  
         if (key->sk_attno > tupnatts)
         {
             /*
              * This attribute is truncated (must be high key).  The value for
              * this attribute in the first non-pivot tuple on the page to the
              * right could be any possible value.  Assume that truncated
              * attribute passes the qual.
              */
             Assert(ScanDirectionIsForward(dir));
             Assert(BTreeTupleIsPivot(tuple));
             continue;
         }
  
         /* row-comparison keys need special processing */
         if (key->sk_flags & SK_ROW_HEADER)
         {
             if (_bt_check_rowcompare(key, tuple, tupnatts, tupdesc, dir,
                                      continuescan))
                 continue;
             return false;
         }
  
         datum = index_getattr(tuple,
                               key->sk_attno,
                               tupdesc,
                               &isNull);
  
         if (key->sk_flags & SK_ISNULL)
         {
             /* Handle IS NULL/NOT NULL tests */
             if (key->sk_flags & SK_SEARCHNULL)
             {
                 if (isNull)
                     continue;   /* tuple satisfies this qual */
             }
             else
             {
                 Assert(key->sk_flags & SK_SEARCHNOTNULL);
                 if (!isNull)
                     continue;   /* tuple satisfies this qual */
             }
  
             /*
              * Tuple fails this qual.  If it's a required qual for the current
              * scan direction, then we can conclude no further tuples will
              * pass, either.
              */
             if ((key->sk_flags & SK_BT_REQFWD) &&
                 ScanDirectionIsForward(dir))
                 *continuescan = false;
             else if ((key->sk_flags & SK_BT_REQBKWD) &&
                      ScanDirectionIsBackward(dir))
                 *continuescan = false;
  
             /*
              * In any case, this indextuple doesn't match the qual.
              */
             return false;
         }
  
         if (isNull)
         {
             if (key->sk_flags & SK_BT_NULLS_FIRST)
             {
                 /*
                  * Since NULLs are sorted before non-NULLs, we know we have
                  * reached the lower limit of the range of values for this
                  * index attr.  On a backward scan, we can stop if this qual
                  * is one of the "must match" subset.  We can stop regardless
                  * of whether the qual is > or <, so long as it's required,
                  * because it's not possible for any future tuples to pass. On
                  * a forward scan, however, we must keep going, because we may
                  * have initially positioned to the start of the index.
                  */
                 if ((key->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
                     ScanDirectionIsBackward(dir))
                     *continuescan = false;
             }
             else
             {
                 /*
                  * Since NULLs are sorted after non-NULLs, we know we have
                  * reached the upper limit of the range of values for this
                  * index attr.  On a forward scan, we can stop if this qual is
                  * one of the "must match" subset.  We can stop regardless of
                  * whether the qual is > or <, so long as it's required,
                  * because it's not possible for any future tuples to pass. On
                  * a backward scan, however, we must keep going, because we
                  * may have initially positioned to the end of the index.
                  */
                 if ((key->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
                     ScanDirectionIsForward(dir))
                     *continuescan = false;
             }
  
             /*
              * In any case, this indextuple doesn't match the qual.
              */
             return false;
         }
  
         test = FunctionCall2Coll(&key->sk_func, key->sk_collation,
                                  datum, key->sk_argument);
  
         if (!DatumGetBool(test))
         {
             /*
              * Tuple fails this qual.  If it's a required qual for the current
              * scan direction, then we can conclude no further tuples will
              * pass, either.
              *
              * Note: because we stop the scan as soon as any required equality
              * qual fails, it is critical that equality quals be used for the
              * initial positioning in _bt_first() when they are available. See
              * comments in _bt_first().
              */
             if ((key->sk_flags & SK_BT_REQFWD) &&
                 ScanDirectionIsForward(dir))
                 *continuescan = false;
             else if ((key->sk_flags & SK_BT_REQBKWD) &&
                      ScanDirectionIsBackward(dir))
                 *continuescan = false;
  
             /*
              * In any case, this indextuple doesn't match the qual.
              */
             return false;
         }
     }
  
     /* If we get here, the tuple passes all index quals. */
     return true;
 }

References _bt_check_rowcompare(), Assert(), BTreeTupleGetNAtts, BTreeTupleIsPivot(), DatumGetBool(), FunctionCall2Coll(), index_getattr(), IndexScanDescData::indexRelation, sort-test::key, BTScanOpaqueData::keyData, BTScanOpaqueData::numberOfKeys, IndexScanDescData::opaque, RelationGetDescr, ScanDirectionIsBackward, ScanDirectionIsForward, SK_BT_NULLS_FIRST, SK_BT_REQBKWD, SK_BT_REQFWD, SK_ISNULL, SK_ROW_HEADER, SK_SEARCHNOTNULL, SK_SEARCHNULL, and test().

Referenced by _bt_readpage().

◆ _bt_compare_array_elements()

static int _bt_compare_array_elements	(	const void *	a,
		const void *	b,
		void *	arg
	)

static

Definition at line 503 of file nbtutils.c.

 {
     Datum       da = *((const Datum *) a);
     Datum       db = *((const Datum *) b);
     BTSortArrayContext *cxt = (BTSortArrayContext *) arg;
     int32       compare;
  
     compare = DatumGetInt32(FunctionCall2Coll(&cxt->flinfo,
                                               cxt->collation,
                                               da, db));
     if (cxt->reverse)
         INVERT_COMPARE_RESULT(compare);
     return compare;
 }

References a, arg, b, BTSortArrayContext::collation, compare(), DatumGetInt32(), BTSortArrayContext::flinfo, FunctionCall2Coll(), INVERT_COMPARE_RESULT, and BTSortArrayContext::reverse.

Referenced by _bt_sort_array_elements().

◆ _bt_compare_scankey_args()

static bool _bt_compare_scankey_args	(	IndexScanDesc	scan,
		ScanKey	op,
		ScanKey	leftarg,
		ScanKey	rightarg,
		bool *	result
	)

static

Definition at line 1039 of file nbtutils.c.

 {
     Relation    rel = scan->indexRelation;
     Oid         lefttype,
                 righttype,
                 optype,
                 opcintype,
                 cmp_op;
     StrategyNumber strat;
  
     /*
      * First, deal with cases where one or both args are NULL.  This should
      * only happen when the scankeys represent IS NULL/NOT NULL conditions.
      */
     if ((leftarg->sk_flags | rightarg->sk_flags) & SK_ISNULL)
     {
         bool        leftnull,
                     rightnull;
  
         if (leftarg->sk_flags & SK_ISNULL)
         {
             Assert(leftarg->sk_flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
             leftnull = true;
         }
         else
             leftnull = false;
         if (rightarg->sk_flags & SK_ISNULL)
         {
             Assert(rightarg->sk_flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
             rightnull = true;
         }
         else
             rightnull = false;
  
         /*
          * We treat NULL as either greater than or less than all other values.
          * Since true > false, the tests below work correctly for NULLS LAST
          * logic.  If the index is NULLS FIRST, we need to flip the strategy.
          */
         strat = op->sk_strategy;
         if (op->sk_flags & SK_BT_NULLS_FIRST)
             strat = BTCommuteStrategyNumber(strat);
  
         switch (strat)
         {
             case BTLessStrategyNumber:
                 *result = (leftnull < rightnull);
                 break;
             case BTLessEqualStrategyNumber:
                 *result = (leftnull <= rightnull);
                 break;
             case BTEqualStrategyNumber:
                 *result = (leftnull == rightnull);
                 break;
             case BTGreaterEqualStrategyNumber:
                 *result = (leftnull >= rightnull);
                 break;
             case BTGreaterStrategyNumber:
                 *result = (leftnull > rightnull);
                 break;
             default:
                 elog(ERROR, "unrecognized StrategyNumber: %d", (int) strat);
                 *result = false;    /* keep compiler quiet */
                 break;
         }
         return true;
     }
  
     /*
      * The opfamily we need to worry about is identified by the index column.
      */
     Assert(leftarg->sk_attno == rightarg->sk_attno);
  
     opcintype = rel->rd_opcintype[leftarg->sk_attno - 1];
  
     /*
      * Determine the actual datatypes of the ScanKey arguments.  We have to
      * support the convention that sk_subtype == InvalidOid means the opclass
      * input type; this is a hack to simplify life for ScanKeyInit().
      */
     lefttype = leftarg->sk_subtype;
     if (lefttype == InvalidOid)
         lefttype = opcintype;
     righttype = rightarg->sk_subtype;
     if (righttype == InvalidOid)
         righttype = opcintype;
     optype = op->sk_subtype;
     if (optype == InvalidOid)
         optype = opcintype;
  
     /*
      * If leftarg and rightarg match the types expected for the "op" scankey,
      * we can use its already-looked-up comparison function.
      */
     if (lefttype == opcintype && righttype == optype)
     {
         *result = DatumGetBool(FunctionCall2Coll(&op->sk_func,
                                                  op->sk_collation,
                                                  leftarg->sk_argument,
                                                  rightarg->sk_argument));
         return true;
     }
  
     /*
      * Otherwise, we need to go to the syscache to find the appropriate
      * operator.  (This cannot result in infinite recursion, since no
      * indexscan initiated by syscache lookup will use cross-data-type
      * operators.)
      *
      * If the sk_strategy was flipped by _bt_fix_scankey_strategy, we have to
      * un-flip it to get the correct opfamily member.
      */
     strat = op->sk_strategy;
     if (op->sk_flags & SK_BT_DESC)
         strat = BTCommuteStrategyNumber(strat);
  
     cmp_op = get_opfamily_member(rel->rd_opfamily[leftarg->sk_attno - 1],
                                  lefttype,
                                  righttype,
                                  strat);
     if (OidIsValid(cmp_op))
     {
         RegProcedure cmp_proc = get_opcode(cmp_op);
  
         if (RegProcedureIsValid(cmp_proc))
         {
             *result = DatumGetBool(OidFunctionCall2Coll(cmp_proc,
                                                         op->sk_collation,
                                                         leftarg->sk_argument,
                                                         rightarg->sk_argument));
             return true;
         }
     }
  
     /* Can't make the comparison */
     *result = false;            /* suppress compiler warnings */
     return false;
 }

References Assert(), BTCommuteStrategyNumber, BTEqualStrategyNumber, BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, DatumGetBool(), elog(), ERROR, FunctionCall2Coll(), get_opcode(), get_opfamily_member(), IndexScanDescData::indexRelation, InvalidOid, OidFunctionCall2Coll(), OidIsValid, RelationData::rd_opcintype, RelationData::rd_opfamily, RegProcedureIsValid, ScanKeyData::sk_argument, ScanKeyData::sk_attno, SK_BT_DESC, SK_BT_NULLS_FIRST, ScanKeyData::sk_collation, ScanKeyData::sk_flags, ScanKeyData::sk_func, SK_ISNULL, SK_SEARCHNOTNULL, SK_SEARCHNULL, ScanKeyData::sk_strategy, and ScanKeyData::sk_subtype.

Referenced by _bt_preprocess_keys().

◆ _bt_end_vacuum()

void _bt_end_vacuum ( Relation rel )

Definition at line 2033 of file nbtutils.c.

 {
     int         i;
  
     LWLockAcquire(BtreeVacuumLock, LW_EXCLUSIVE);
  
     /* Find the array entry */
     for (i = 0; i < btvacinfo->num_vacuums; i++)
     {
         BTOneVacInfo *vac = &btvacinfo->vacuums[i];
  
         if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
             vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
         {
             /* Remove it by shifting down the last entry */
             *vac = btvacinfo->vacuums[btvacinfo->num_vacuums - 1];
             btvacinfo->num_vacuums--;
             break;
         }
     }
  
     LWLockRelease(BtreeVacuumLock);
 }

References btvacinfo, LockRelId::dbId, i, LockInfoData::lockRelId, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), BTVacInfo::num_vacuums, RelationData::rd_lockInfo, BTOneVacInfo::relid, LockRelId::relId, and BTVacInfo::vacuums.

Referenced by _bt_end_vacuum_callback(), and btbulkdelete().

◆ _bt_end_vacuum_callback()

void _bt_end_vacuum_callback	(	int	code,
		Datum	arg
	)

Definition at line 2061 of file nbtutils.c.

 {
     _bt_end_vacuum((Relation) DatumGetPointer(arg));
 }

References _bt_end_vacuum(), arg, and DatumGetPointer().

Referenced by btbulkdelete().

◆ _bt_find_extreme_element()

static Datum _bt_find_extreme_element	(	IndexScanDesc	scan,
		ScanKey	skey,
		StrategyNumber	strat,
		Datum *	elems,
		int	nelems
	)

static

Definition at line 382 of file nbtutils.c.

 {
     Relation    rel = scan->indexRelation;
     Oid         elemtype,
                 cmp_op;
     RegProcedure cmp_proc;
     FmgrInfo    flinfo;
     Datum       result;
     int         i;
  
     /*
      * Determine the nominal datatype of the array elements.  We have to
      * support the convention that sk_subtype == InvalidOid means the opclass
      * input type; this is a hack to simplify life for ScanKeyInit().
      */
     elemtype = skey->sk_subtype;
     if (elemtype == InvalidOid)
         elemtype = rel->rd_opcintype[skey->sk_attno - 1];
  
     /*
      * Look up the appropriate comparison operator in the opfamily.
      *
      * Note: it's possible that this would fail, if the opfamily is
      * incomplete, but it seems quite unlikely that an opfamily would omit
      * non-cross-type comparison operators for any datatype that it supports
      * at all.
      */
     cmp_op = get_opfamily_member(rel->rd_opfamily[skey->sk_attno - 1],
                                  elemtype,
                                  elemtype,
                                  strat);
     if (!OidIsValid(cmp_op))
         elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
              strat, elemtype, elemtype,
              rel->rd_opfamily[skey->sk_attno - 1]);
     cmp_proc = get_opcode(cmp_op);
     if (!RegProcedureIsValid(cmp_proc))
         elog(ERROR, "missing oprcode for operator %u", cmp_op);
  
     fmgr_info(cmp_proc, &flinfo);
  
     Assert(nelems > 0);
     result = elems[0];
     for (i = 1; i < nelems; i++)
     {
         if (DatumGetBool(FunctionCall2Coll(&flinfo,
                                            skey->sk_collation,
                                            elems[i],
                                            result)))
             result = elems[i];
     }
  
     return result;
 }

References Assert(), DatumGetBool(), elog(), ERROR, fmgr_info(), FunctionCall2Coll(), get_opcode(), get_opfamily_member(), i, IndexScanDescData::indexRelation, InvalidOid, OidIsValid, RelationData::rd_opcintype, RelationData::rd_opfamily, RegProcedureIsValid, ScanKeyData::sk_attno, ScanKeyData::sk_collation, and ScanKeyData::sk_subtype.

Referenced by _bt_preprocess_array_keys().

◆ _bt_fix_scankey_strategy()

static bool _bt_fix_scankey_strategy	(	ScanKey	skey,
		int16 *	indoption
	)

static

Definition at line 1203 of file nbtutils.c.

 {
     int         addflags;
  
     addflags = indoption[skey->sk_attno - 1] << SK_BT_INDOPTION_SHIFT;
  
     /*
      * We treat all btree operators as strict (even if they're not so marked
      * in pg_proc). This means that it is impossible for an operator condition
      * with a NULL comparison constant to succeed, and we can reject it right
      * away.
      *
      * However, we now also support "x IS NULL" clauses as search conditions,
      * so in that case keep going. The planner has not filled in any
      * particular strategy in this case, so set it to BTEqualStrategyNumber
      * --- we can treat IS NULL as an equality operator for purposes of search
      * strategy.
      *
      * Likewise, "x IS NOT NULL" is supported.  We treat that as either "less
      * than NULL" in a NULLS LAST index, or "greater than NULL" in a NULLS
      * FIRST index.
      *
      * Note: someday we might have to fill in sk_collation from the index
      * column's collation.  At the moment this is a non-issue because we'll
      * never actually call the comparison operator on a NULL.
      */
     if (skey->sk_flags & SK_ISNULL)
     {
         /* SK_ISNULL shouldn't be set in a row header scankey */
         Assert(!(skey->sk_flags & SK_ROW_HEADER));
  
         /* Set indoption flags in scankey (might be done already) */
         skey->sk_flags |= addflags;
  
         /* Set correct strategy for IS NULL or NOT NULL search */
         if (skey->sk_flags & SK_SEARCHNULL)
         {
             skey->sk_strategy = BTEqualStrategyNumber;
             skey->sk_subtype = InvalidOid;
             skey->sk_collation = InvalidOid;
         }
         else if (skey->sk_flags & SK_SEARCHNOTNULL)
         {
             if (skey->sk_flags & SK_BT_NULLS_FIRST)
                 skey->sk_strategy = BTGreaterStrategyNumber;
             else
                 skey->sk_strategy = BTLessStrategyNumber;
             skey->sk_subtype = InvalidOid;
             skey->sk_collation = InvalidOid;
         }
         else
         {
             /* regular qual, so it cannot be satisfied */
             return false;
         }
  
         /* Needn't do the rest */
         return true;
     }
  
     /* Adjust strategy for DESC, if we didn't already */
     if ((addflags & SK_BT_DESC) && !(skey->sk_flags & SK_BT_DESC))
         skey->sk_strategy = BTCommuteStrategyNumber(skey->sk_strategy);
     skey->sk_flags |= addflags;
  
     /* If it's a row header, fix row member flags and strategies similarly */
     if (skey->sk_flags & SK_ROW_HEADER)
     {
         ScanKey     subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
  
         for (;;)
         {
             Assert(subkey->sk_flags & SK_ROW_MEMBER);
             addflags = indoption[subkey->sk_attno - 1] << SK_BT_INDOPTION_SHIFT;
             if ((addflags & SK_BT_DESC) && !(subkey->sk_flags & SK_BT_DESC))
                 subkey->sk_strategy = BTCommuteStrategyNumber(subkey->sk_strategy);
             subkey->sk_flags |= addflags;
             if (subkey->sk_flags & SK_ROW_END)
                 break;
             subkey++;
         }
     }
  
     return true;
 }

References Assert(), BTCommuteStrategyNumber, BTEqualStrategyNumber, BTGreaterStrategyNumber, BTLessStrategyNumber, DatumGetPointer(), InvalidOid, ScanKeyData::sk_argument, ScanKeyData::sk_attno, SK_BT_DESC, SK_BT_INDOPTION_SHIFT, SK_BT_NULLS_FIRST, ScanKeyData::sk_collation, ScanKeyData::sk_flags, SK_ISNULL, SK_ROW_END, SK_ROW_HEADER, SK_ROW_MEMBER, SK_SEARCHNOTNULL, SK_SEARCHNULL, ScanKeyData::sk_strategy, and ScanKeyData::sk_subtype.

Referenced by _bt_preprocess_keys().

◆ _bt_freestack()

void _bt_freestack ( BTStack stack )

Definition at line 182 of file nbtutils.c.

 {
     BTStack     ostack;
  
     while (stack != NULL)
     {
         ostack = stack;
         stack = stack->bts_parent;
         pfree(ostack);
     }
 }

References BTStackData::bts_parent, and pfree().

Referenced by _bt_doinsert(), _bt_first(), and bt_rootdescend().

◆ _bt_keep_natts()

static int _bt_keep_natts	(	Relation	rel,
		IndexTuple	lastleft,
		IndexTuple	firstright,
		BTScanInsert	itup_key
	)

static

Definition at line 2350 of file nbtutils.c.

 {
     int         nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
     TupleDesc   itupdesc = RelationGetDescr(rel);
     int         keepnatts;
     ScanKey     scankey;
  
     /*
      * _bt_compare() treats truncated key attributes as having the value minus
      * infinity, which would break searches within !heapkeyspace indexes.  We
      * must still truncate away non-key attribute values, though.
      */
     if (!itup_key->heapkeyspace)
         return nkeyatts;
  
     scankey = itup_key->scankeys;
     keepnatts = 1;
     for (int attnum = 1; attnum <= nkeyatts; attnum++, scankey++)
     {
         Datum       datum1,
                     datum2;
         bool        isNull1,
                     isNull2;
  
         datum1 = index_getattr(lastleft, attnum, itupdesc, &isNull1);
         datum2 = index_getattr(firstright, attnum, itupdesc, &isNull2);
  
         if (isNull1 != isNull2)
             break;
  
         if (!isNull1 &&
             DatumGetInt32(FunctionCall2Coll(&scankey->sk_func,
                                             scankey->sk_collation,
                                             datum1,
                                             datum2)) != 0)
             break;
  
         keepnatts++;
     }
  
     /*
      * Assert that _bt_keep_natts_fast() agrees with us in passing.  This is
      * expected in an allequalimage index.
      */
     Assert(!itup_key->allequalimage ||
            keepnatts == _bt_keep_natts_fast(rel, lastleft, firstright));
  
     return keepnatts;
 }

References _bt_keep_natts_fast(), BTScanInsertData::allequalimage, Assert(), attnum, DatumGetInt32(), FunctionCall2Coll(), BTScanInsertData::heapkeyspace, index_getattr(), IndexRelationGetNumberOfKeyAttributes, RelationGetDescr, BTScanInsertData::scankeys, ScanKeyData::sk_collation, and ScanKeyData::sk_func.

Referenced by _bt_truncate().

◆ _bt_keep_natts_fast()

int _bt_keep_natts_fast	(	Relation	rel,
		IndexTuple	lastleft,
		IndexTuple	firstright
	)

Definition at line 2424 of file nbtutils.c.

 {
     TupleDesc   itupdesc = RelationGetDescr(rel);
     int         keysz = IndexRelationGetNumberOfKeyAttributes(rel);
     int         keepnatts;
  
     keepnatts = 1;
     for (int attnum = 1; attnum <= keysz; attnum++)
     {
         Datum       datum1,
                     datum2;
         bool        isNull1,
                     isNull2;
         Form_pg_attribute att;
  
         datum1 = index_getattr(lastleft, attnum, itupdesc, &isNull1);
         datum2 = index_getattr(firstright, attnum, itupdesc, &isNull2);
         att = TupleDescAttr(itupdesc, attnum - 1);
  
         if (isNull1 != isNull2)
             break;
  
         if (!isNull1 &&
             !datum_image_eq(datum1, datum2, att->attbyval, att->attlen))
             break;
  
         keepnatts++;
     }
  
     return keepnatts;
 }

References attnum, datum_image_eq(), index_getattr(), IndexRelationGetNumberOfKeyAttributes, RelationGetDescr, and TupleDescAttr.

Referenced by _bt_afternewitemoff(), _bt_bottomupdel_pass(), _bt_dedup_pass(), _bt_do_singleval(), _bt_keep_natts(), _bt_load(), _bt_split_penalty(), and _bt_strategy().

◆ _bt_killitems()

void _bt_killitems ( IndexScanDesc scan )

Definition at line 1725 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     Page        page;
     BTPageOpaque opaque;
     OffsetNumber minoff;
     OffsetNumber maxoff;
     int         i;
     int         numKilled = so->numKilled;
     bool        killedsomething = false;
     bool        droppedpin PG_USED_FOR_ASSERTS_ONLY;
  
     Assert(BTScanPosIsValid(so->currPos));
  
     /*
      * Always reset the scan state, so we don't look for same items on other
      * pages.
      */
     so->numKilled = 0;
  
     if (BTScanPosIsPinned(so->currPos))
     {
         /*
          * We have held the pin on this page since we read the index tuples,
          * so all we need to do is lock it.  The pin will have prevented
          * re-use of any TID on the page, so there is no need to check the
          * LSN.
          */
         droppedpin = false;
         _bt_lockbuf(scan->indexRelation, so->currPos.buf, BT_READ);
  
         page = BufferGetPage(so->currPos.buf);
     }
     else
     {
         Buffer      buf;
  
         droppedpin = true;
         /* Attempt to re-read the buffer, getting pin and lock. */
         buf = _bt_getbuf(scan->indexRelation, so->currPos.currPage, BT_READ);
  
         page = BufferGetPage(buf);
         if (BufferGetLSNAtomic(buf) == so->currPos.lsn)
             so->currPos.buf = buf;
         else
         {
             /* Modified while not pinned means hinting is not safe. */
             _bt_relbuf(scan->indexRelation, buf);
             return;
         }
     }
  
     opaque = BTPageGetOpaque(page);
     minoff = P_FIRSTDATAKEY(opaque);
     maxoff = PageGetMaxOffsetNumber(page);
  
     for (i = 0; i < numKilled; i++)
     {
         int         itemIndex = so->killedItems[i];
         BTScanPosItem *kitem = &so->currPos.items[itemIndex];
         OffsetNumber offnum = kitem->indexOffset;
  
         Assert(itemIndex >= so->currPos.firstItem &&
                itemIndex <= so->currPos.lastItem);
         if (offnum < minoff)
             continue;           /* pure paranoia */
         while (offnum <= maxoff)
         {
             ItemId      iid = PageGetItemId(page, offnum);
             IndexTuple  ituple = (IndexTuple) PageGetItem(page, iid);
             bool        killtuple = false;
  
             if (BTreeTupleIsPosting(ituple))
             {
                 int         pi = i + 1;
                 int         nposting = BTreeTupleGetNPosting(ituple);
                 int         j;
  
                 /*
                  * We rely on the convention that heap TIDs in the scanpos
                  * items array are stored in ascending heap TID order for a
                  * group of TIDs that originally came from a posting list
                  * tuple.  This convention even applies during backwards
                  * scans, where returning the TIDs in descending order might
                  * seem more natural.  This is about effectiveness, not
                  * correctness.
                  *
                  * Note that the page may have been modified in almost any way
                  * since we first read it (in the !droppedpin case), so it's
                  * possible that this posting list tuple wasn't a posting list
                  * tuple when we first encountered its heap TIDs.
                  */
                 for (j = 0; j < nposting; j++)
                 {
                     ItemPointer item = BTreeTupleGetPostingN(ituple, j);
  
                     if (!ItemPointerEquals(item, &kitem->heapTid))
                         break;  /* out of posting list loop */
  
                     /*
                      * kitem must have matching offnum when heap TIDs match,
                      * though only in the common case where the page can't
                      * have been concurrently modified
                      */
                     Assert(kitem->indexOffset == offnum || !droppedpin);
  
                     /*
                      * Read-ahead to later kitems here.
                      *
                      * We rely on the assumption that not advancing kitem here
                      * will prevent us from considering the posting list tuple
                      * fully dead by not matching its next heap TID in next
                      * loop iteration.
                      *
                      * If, on the other hand, this is the final heap TID in
                      * the posting list tuple, then tuple gets killed
                      * regardless (i.e. we handle the case where the last
                      * kitem is also the last heap TID in the last index tuple
                      * correctly -- posting tuple still gets killed).
                      */
                     if (pi < numKilled)
                         kitem = &so->currPos.items[so->killedItems[pi++]];
                 }
  
                 /*
                  * Don't bother advancing the outermost loop's int iterator to
                  * avoid processing killed items that relate to the same
                  * offnum/posting list tuple.  This micro-optimization hardly
                  * seems worth it.  (Further iterations of the outermost loop
                  * will fail to match on this same posting list's first heap
                  * TID instead, so we'll advance to the next offnum/index
                  * tuple pretty quickly.)
                  */
                 if (j == nposting)
                     killtuple = true;
             }
             else if (ItemPointerEquals(&ituple->t_tid, &kitem->heapTid))
                 killtuple = true;
  
             /*
              * Mark index item as dead, if it isn't already.  Since this
              * happens while holding a buffer lock possibly in shared mode,
              * it's possible that multiple processes attempt to do this
              * simultaneously, leading to multiple full-page images being sent
              * to WAL (if wal_log_hints or data checksums are enabled), which
              * is undesirable.
              */
             if (killtuple && !ItemIdIsDead(iid))
             {
                 /* found the item/all posting list items */
                 ItemIdMarkDead(iid);
                 killedsomething = true;
                 break;          /* out of inner search loop */
             }
             offnum = OffsetNumberNext(offnum);
         }
     }
  
     /*
      * Since this can be redone later if needed, mark as dirty hint.
      *
      * Whenever we mark anything LP_DEAD, we also set the page's
      * BTP_HAS_GARBAGE flag, which is likewise just a hint.  (Note that we
      * only rely on the page-level flag in !heapkeyspace indexes.)
      */
     if (killedsomething)
     {
         opaque->btpo_flags |= BTP_HAS_GARBAGE;
         MarkBufferDirtyHint(so->currPos.buf, true);
     }
  
     _bt_unlockbuf(scan->indexRelation, so->currPos.buf);
 }

References _bt_getbuf(), _bt_lockbuf(), _bt_relbuf(), _bt_unlockbuf(), Assert(), BT_READ, BTP_HAS_GARBAGE, BTPageGetOpaque, BTreeTupleGetNPosting(), BTreeTupleGetPostingN(), BTreeTupleIsPosting(), BTScanPosIsPinned, BTScanPosIsValid, buf, BTScanPosData::buf, BufferGetLSNAtomic(), BufferGetPage(), BTScanPosData::currPage, BTScanOpaqueData::currPos, BTScanPosData::firstItem, BTScanPosItem::heapTid, i, BTScanPosItem::indexOffset, IndexScanDescData::indexRelation, ItemIdIsDead, ItemIdMarkDead, ItemPointerEquals(), BTScanPosData::items, j, BTScanOpaqueData::killedItems, BTScanPosData::lsn, MarkBufferDirtyHint(), BTScanOpaqueData::numKilled, OffsetNumberNext, IndexScanDescData::opaque, P_FIRSTDATAKEY, PageGetItem(), PageGetItemId(), PageGetMaxOffsetNumber(), PG_USED_FOR_ASSERTS_ONLY, and IndexTupleData::t_tid.

Referenced by _bt_steppage(), btendscan(), btrescan(), and btrestrpos().

◆ _bt_mark_array_keys()

void _bt_mark_array_keys ( IndexScanDesc scan )

Definition at line 610 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     int         i;
  
     for (i = 0; i < so->numArrayKeys; i++)
     {
         BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
  
         curArrayKey->mark_elem = curArrayKey->cur_elem;
     }
 }

References BTScanOpaqueData::arrayKeys, BTArrayKeyInfo::cur_elem, i, BTArrayKeyInfo::mark_elem, BTScanOpaqueData::numArrayKeys, and IndexScanDescData::opaque.

◆ _bt_mark_scankey_required()

static void _bt_mark_scankey_required ( ScanKey skey )

static

Definition at line 1305 of file nbtutils.c.

 {
     int         addflags;
  
     switch (skey->sk_strategy)
     {
         case BTLessStrategyNumber:
         case BTLessEqualStrategyNumber:
             addflags = SK_BT_REQFWD;
             break;
         case BTEqualStrategyNumber:
             addflags = SK_BT_REQFWD | SK_BT_REQBKWD;
             break;
         case BTGreaterEqualStrategyNumber:
         case BTGreaterStrategyNumber:
             addflags = SK_BT_REQBKWD;
             break;
         default:
             elog(ERROR, "unrecognized StrategyNumber: %d",
                  (int) skey->sk_strategy);
             addflags = 0;       /* keep compiler quiet */
             break;
     }
  
     skey->sk_flags |= addflags;
  
     if (skey->sk_flags & SK_ROW_HEADER)
     {
         ScanKey     subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
  
         /* First subkey should be same column/operator as the header */
         Assert(subkey->sk_flags & SK_ROW_MEMBER);
         Assert(subkey->sk_attno == skey->sk_attno);
         Assert(subkey->sk_strategy == skey->sk_strategy);
         subkey->sk_flags |= addflags;
     }
 }

References Assert(), BTEqualStrategyNumber, BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, DatumGetPointer(), elog(), ERROR, ScanKeyData::sk_argument, ScanKeyData::sk_attno, SK_BT_REQBKWD, SK_BT_REQFWD, ScanKeyData::sk_flags, SK_ROW_HEADER, SK_ROW_MEMBER, and ScanKeyData::sk_strategy.

Referenced by _bt_preprocess_keys().

◆ _bt_mkscankey()

BTScanInsert _bt_mkscankey	(	Relation	rel,
		IndexTuple	itup
	)

Definition at line 90 of file nbtutils.c.

 {
     BTScanInsert key;
     ScanKey     skey;
     TupleDesc   itupdesc;
     int         indnkeyatts;
     int16      *indoption;
     int         tupnatts;
     int         i;
  
     itupdesc = RelationGetDescr(rel);
     indnkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
     indoption = rel->rd_indoption;
     tupnatts = itup ? BTreeTupleGetNAtts(itup, rel) : 0;
  
     Assert(tupnatts <= IndexRelationGetNumberOfAttributes(rel));
  
     /*
      * We'll execute search using scan key constructed on key columns.
      * Truncated attributes and non-key attributes are omitted from the final
      * scan key.
      */
     key = palloc(offsetof(BTScanInsertData, scankeys) +
                  sizeof(ScanKeyData) * indnkeyatts);
     if (itup)
         _bt_metaversion(rel, &key->heapkeyspace, &key->allequalimage);
     else
     {
         /* Utility statement callers can set these fields themselves */
         key->heapkeyspace = true;
         key->allequalimage = false;
     }
     key->anynullkeys = false;   /* initial assumption */
     key->nextkey = false;
     key->pivotsearch = false;
     key->keysz = Min(indnkeyatts, tupnatts);
     key->scantid = key->heapkeyspace && itup ?
         BTreeTupleGetHeapTID(itup) : NULL;
     skey = key->scankeys;
     for (i = 0; i < indnkeyatts; i++)
     {
         FmgrInfo   *procinfo;
         Datum       arg;
         bool        null;
         int         flags;
  
         /*
          * We can use the cached (default) support procs since no cross-type
          * comparison can be needed.
          */
         procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);
  
         /*
          * Key arguments built from truncated attributes (or when caller
          * provides no tuple) are defensively represented as NULL values. They
          * should never be used.
          */
         if (i < tupnatts)
             arg = index_getattr(itup, i + 1, itupdesc, &null);
         else
         {
             arg = (Datum) 0;
             null = true;
         }
         flags = (null ? SK_ISNULL : 0) | (indoption[i] << SK_BT_INDOPTION_SHIFT);
         ScanKeyEntryInitializeWithInfo(&skey[i],
                                        flags,
                                        (AttrNumber) (i + 1),
                                        InvalidStrategy,
                                        InvalidOid,
                                        rel->rd_indcollation[i],
                                        procinfo,
                                        arg);
         /* Record if any key attribute is NULL (or truncated) */
         if (null)
             key->anynullkeys = true;
     }
  
     /*
      * In NULLS NOT DISTINCT mode, we pretend that there are no null keys, so
      * that full uniqueness check is done.
      */
     if (rel->rd_index->indnullsnotdistinct)
         key->anynullkeys = false;
  
     return key;
 }

References _bt_metaversion(), arg, Assert(), BTORDER_PROC, BTreeTupleGetHeapTID(), BTreeTupleGetNAtts, i, index_getattr(), index_getprocinfo(), IndexRelationGetNumberOfAttributes, IndexRelationGetNumberOfKeyAttributes, InvalidOid, InvalidStrategy, sort-test::key, Min, palloc(), RelationData::rd_indcollation, RelationData::rd_index, RelationData::rd_indoption, RelationGetDescr, ScanKeyEntryInitializeWithInfo(), SK_BT_INDOPTION_SHIFT, and SK_ISNULL.

Referenced by _bt_doinsert(), _bt_leafbuild(), _bt_pagedel(), bt_mkscankey_pivotsearch(), bt_rootdescend(), tuplesort_begin_cluster(), and tuplesort_begin_index_btree().

◆ _bt_preprocess_array_keys()

void _bt_preprocess_array_keys ( IndexScanDesc scan )

Definition at line 210 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     int         numberOfKeys = scan->numberOfKeys;
     int16      *indoption = scan->indexRelation->rd_indoption;
     int         numArrayKeys;
     ScanKey     cur;
     int         i;
     MemoryContext oldContext;
  
     /* Quick check to see if there are any array keys */
     numArrayKeys = 0;
     for (i = 0; i < numberOfKeys; i++)
     {
         cur = &scan->keyData[i];
         if (cur->sk_flags & SK_SEARCHARRAY)
         {
             numArrayKeys++;
             Assert(!(cur->sk_flags & (SK_ROW_HEADER | SK_SEARCHNULL | SK_SEARCHNOTNULL)));
             /* If any arrays are null as a whole, we can quit right now. */
             if (cur->sk_flags & SK_ISNULL)
             {
                 so->numArrayKeys = -1;
                 so->arrayKeyData = NULL;
                 return;
             }
         }
     }
  
     /* Quit if nothing to do. */
     if (numArrayKeys == 0)
     {
         so->numArrayKeys = 0;
         so->arrayKeyData = NULL;
         return;
     }
  
     /*
      * Make a scan-lifespan context to hold array-associated data, or reset it
      * if we already have one from a previous rescan cycle.
      */
     if (so->arrayContext == NULL)
         so->arrayContext = AllocSetContextCreate(CurrentMemoryContext,
                                                  "BTree array context",
                                                  ALLOCSET_SMALL_SIZES);
     else
         MemoryContextReset(so->arrayContext);
  
     oldContext = MemoryContextSwitchTo(so->arrayContext);
  
     /* Create modifiable copy of scan->keyData in the workspace context */
     so->arrayKeyData = (ScanKey) palloc(scan->numberOfKeys * sizeof(ScanKeyData));
     memcpy(so->arrayKeyData,
            scan->keyData,
            scan->numberOfKeys * sizeof(ScanKeyData));
  
     /* Allocate space for per-array data in the workspace context */
     so->arrayKeys = (BTArrayKeyInfo *) palloc0(numArrayKeys * sizeof(BTArrayKeyInfo));
  
     /* Now process each array key */
     numArrayKeys = 0;
     for (i = 0; i < numberOfKeys; i++)
     {
         ArrayType  *arrayval;
         int16       elmlen;
         bool        elmbyval;
         char        elmalign;
         int         num_elems;
         Datum      *elem_values;
         bool       *elem_nulls;
         int         num_nonnulls;
         int         j;
  
         cur = &so->arrayKeyData[i];
         if (!(cur->sk_flags & SK_SEARCHARRAY))
             continue;
  
         /*
          * First, deconstruct the array into elements.  Anything allocated
          * here (including a possibly detoasted array value) is in the
          * workspace context.
          */
         arrayval = DatumGetArrayTypeP(cur->sk_argument);
         /* We could cache this data, but not clear it's worth it */
         get_typlenbyvalalign(ARR_ELEMTYPE(arrayval),
                              &elmlen, &elmbyval, &elmalign);
         deconstruct_array(arrayval,
                           ARR_ELEMTYPE(arrayval),
                           elmlen, elmbyval, elmalign,
                           &elem_values, &elem_nulls, &num_elems);
  
         /*
          * Compress out any null elements.  We can ignore them since we assume
          * all btree operators are strict.
          */
         num_nonnulls = 0;
         for (j = 0; j < num_elems; j++)
         {
             if (!elem_nulls[j])
                 elem_values[num_nonnulls++] = elem_values[j];
         }
  
         /* We could pfree(elem_nulls) now, but not worth the cycles */
  
         /* If there's no non-nulls, the scan qual is unsatisfiable */
         if (num_nonnulls == 0)
         {
             numArrayKeys = -1;
             break;
         }
  
         /*
          * If the comparison operator is not equality, then the array qual
          * degenerates to a simple comparison against the smallest or largest
          * non-null array element, as appropriate.
          */
         switch (cur->sk_strategy)
         {
             case BTLessStrategyNumber:
             case BTLessEqualStrategyNumber:
                 cur->sk_argument =
                     _bt_find_extreme_element(scan, cur,
                                              BTGreaterStrategyNumber,
                                              elem_values, num_nonnulls);
                 continue;
             case BTEqualStrategyNumber:
                 /* proceed with rest of loop */
                 break;
             case BTGreaterEqualStrategyNumber:
             case BTGreaterStrategyNumber:
                 cur->sk_argument =
                     _bt_find_extreme_element(scan, cur,
                                              BTLessStrategyNumber,
                                              elem_values, num_nonnulls);
                 continue;
             default:
                 elog(ERROR, "unrecognized StrategyNumber: %d",
                      (int) cur->sk_strategy);
                 break;
         }
  
         /*
          * Sort the non-null elements and eliminate any duplicates.  We must
          * sort in the same ordering used by the index column, so that the
          * successive primitive indexscans produce data in index order.
          */
         num_elems = _bt_sort_array_elements(scan, cur,
                                             (indoption[cur->sk_attno - 1] & INDOPTION_DESC) != 0,
                                             elem_values, num_nonnulls);
  
         /*
          * And set up the BTArrayKeyInfo data.
          */
         so->arrayKeys[numArrayKeys].scan_key = i;
         so->arrayKeys[numArrayKeys].num_elems = num_elems;
         so->arrayKeys[numArrayKeys].elem_values = elem_values;
         numArrayKeys++;
     }
  
     so->numArrayKeys = numArrayKeys;
  
     MemoryContextSwitchTo(oldContext);
 }

References _bt_find_extreme_element(), _bt_sort_array_elements(), ALLOCSET_SMALL_SIZES, AllocSetContextCreate, ARR_ELEMTYPE, BTScanOpaqueData::arrayContext, BTScanOpaqueData::arrayKeyData, BTScanOpaqueData::arrayKeys, Assert(), BTEqualStrategyNumber, BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, cur, CurrentMemoryContext, DatumGetArrayTypeP, deconstruct_array(), BTArrayKeyInfo::elem_values, elog(), ERROR, get_typlenbyvalalign(), i, IndexScanDescData::indexRelation, j, IndexScanDescData::keyData, MemoryContextReset(), MemoryContextSwitchTo(), BTArrayKeyInfo::num_elems, BTScanOpaqueData::numArrayKeys, IndexScanDescData::numberOfKeys, IndexScanDescData::opaque, palloc(), palloc0(), RelationData::rd_indoption, BTArrayKeyInfo::scan_key, SK_ISNULL, SK_ROW_HEADER, SK_SEARCHARRAY, SK_SEARCHNOTNULL, and SK_SEARCHNULL.

Referenced by btrescan().

◆ _bt_preprocess_keys()

void _bt_preprocess_keys ( IndexScanDesc scan )

Definition at line 749 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     int         numberOfKeys = scan->numberOfKeys;
     int16      *indoption = scan->indexRelation->rd_indoption;
     int         new_numberOfKeys;
     int         numberOfEqualCols;
     ScanKey     inkeys;
     ScanKey     outkeys;
     ScanKey     cur;
     ScanKey     xform[BTMaxStrategyNumber];
     bool        test_result;
     int         i,
                 j;
     AttrNumber  attno;
  
     /* initialize result variables */
     so->qual_ok = true;
     so->numberOfKeys = 0;
  
     if (numberOfKeys < 1)
         return;                 /* done if qual-less scan */
  
     /*
      * Read so->arrayKeyData if array keys are present, else scan->keyData
      */
     if (so->arrayKeyData != NULL)
         inkeys = so->arrayKeyData;
     else
         inkeys = scan->keyData;
  
     outkeys = so->keyData;
     cur = &inkeys[0];
     /* we check that input keys are correctly ordered */
     if (cur->sk_attno < 1)
         elog(ERROR, "btree index keys must be ordered by attribute");
  
     /* We can short-circuit most of the work if there's just one key */
     if (numberOfKeys == 1)
     {
         /* Apply indoption to scankey (might change sk_strategy!) */
         if (!_bt_fix_scankey_strategy(cur, indoption))
             so->qual_ok = false;
         memcpy(outkeys, cur, sizeof(ScanKeyData));
         so->numberOfKeys = 1;
         /* We can mark the qual as required if it's for first index col */
         if (cur->sk_attno == 1)
             _bt_mark_scankey_required(outkeys);
         return;
     }
  
     /*
      * Otherwise, do the full set of pushups.
      */
     new_numberOfKeys = 0;
     numberOfEqualCols = 0;
  
     /*
      * Initialize for processing of keys for attr 1.
      *
      * xform[i] points to the currently best scan key of strategy type i+1; it
      * is NULL if we haven't yet found such a key for this attr.
      */
     attno = 1;
     memset(xform, 0, sizeof(xform));
  
     /*
      * Loop iterates from 0 to numberOfKeys inclusive; we use the last pass to
      * handle after-last-key processing.  Actual exit from the loop is at the
      * "break" statement below.
      */
     for (i = 0;; cur++, i++)
     {
         if (i < numberOfKeys)
         {
             /* Apply indoption to scankey (might change sk_strategy!) */
             if (!_bt_fix_scankey_strategy(cur, indoption))
             {
                 /* NULL can't be matched, so give up */
                 so->qual_ok = false;
                 return;
             }
         }
  
         /*
          * If we are at the end of the keys for a particular attr, finish up
          * processing and emit the cleaned-up keys.
          */
         if (i == numberOfKeys || cur->sk_attno != attno)
         {
             int         priorNumberOfEqualCols = numberOfEqualCols;
  
             /* check input keys are correctly ordered */
             if (i < numberOfKeys && cur->sk_attno < attno)
                 elog(ERROR, "btree index keys must be ordered by attribute");
  
             /*
              * If = has been specified, all other keys can be eliminated as
              * redundant.  If we have a case like key = 1 AND key > 2, we can
              * set qual_ok to false and abandon further processing.
              *
              * We also have to deal with the case of "key IS NULL", which is
              * unsatisfiable in combination with any other index condition. By
              * the time we get here, that's been classified as an equality
              * check, and we've rejected any combination of it with a regular
              * equality condition; but not with other types of conditions.
              */
             if (xform[BTEqualStrategyNumber - 1])
             {
                 ScanKey     eq = xform[BTEqualStrategyNumber - 1];
  
                 for (j = BTMaxStrategyNumber; --j >= 0;)
                 {
                     ScanKey     chk = xform[j];
  
                     if (!chk || j == (BTEqualStrategyNumber - 1))
                         continue;
  
                     if (eq->sk_flags & SK_SEARCHNULL)
                     {
                         /* IS NULL is contradictory to anything else */
                         so->qual_ok = false;
                         return;
                     }
  
                     if (_bt_compare_scankey_args(scan, chk, eq, chk,
                                                  &test_result))
                     {
                         if (!test_result)
                         {
                             /* keys proven mutually contradictory */
                             so->qual_ok = false;
                             return;
                         }
                         /* else discard the redundant non-equality key */
                         xform[j] = NULL;
                     }
                     /* else, cannot determine redundancy, keep both keys */
                 }
                 /* track number of attrs for which we have "=" keys */
                 numberOfEqualCols++;
             }
  
             /* try to keep only one of <, <= */
             if (xform[BTLessStrategyNumber - 1]
                 && xform[BTLessEqualStrategyNumber - 1])
             {
                 ScanKey     lt = xform[BTLessStrategyNumber - 1];
                 ScanKey     le = xform[BTLessEqualStrategyNumber - 1];
  
                 if (_bt_compare_scankey_args(scan, le, lt, le,
                                              &test_result))
                 {
                     if (test_result)
                         xform[BTLessEqualStrategyNumber - 1] = NULL;
                     else
                         xform[BTLessStrategyNumber - 1] = NULL;
                 }
             }
  
             /* try to keep only one of >, >= */
             if (xform[BTGreaterStrategyNumber - 1]
                 && xform[BTGreaterEqualStrategyNumber - 1])
             {
                 ScanKey     gt = xform[BTGreaterStrategyNumber - 1];
                 ScanKey     ge = xform[BTGreaterEqualStrategyNumber - 1];
  
                 if (_bt_compare_scankey_args(scan, ge, gt, ge,
                                              &test_result))
                 {
                     if (test_result)
                         xform[BTGreaterEqualStrategyNumber - 1] = NULL;
                     else
                         xform[BTGreaterStrategyNumber - 1] = NULL;
                 }
             }
  
             /*
              * Emit the cleaned-up keys into the outkeys[] array, and then
              * mark them if they are required.  They are required (possibly
              * only in one direction) if all attrs before this one had "=".
              */
             for (j = BTMaxStrategyNumber; --j >= 0;)
             {
                 if (xform[j])
                 {
                     ScanKey     outkey = &outkeys[new_numberOfKeys++];
  
                     memcpy(outkey, xform[j], sizeof(ScanKeyData));
                     if (priorNumberOfEqualCols == attno - 1)
                         _bt_mark_scankey_required(outkey);
                 }
             }
  
             /*
              * Exit loop here if done.
              */
             if (i == numberOfKeys)
                 break;
  
             /* Re-initialize for new attno */
             attno = cur->sk_attno;
             memset(xform, 0, sizeof(xform));
         }
  
         /* check strategy this key's operator corresponds to */
         j = cur->sk_strategy - 1;
  
         /* if row comparison, push it directly to the output array */
         if (cur->sk_flags & SK_ROW_HEADER)
         {
             ScanKey     outkey = &outkeys[new_numberOfKeys++];
  
             memcpy(outkey, cur, sizeof(ScanKeyData));
             if (numberOfEqualCols == attno - 1)
                 _bt_mark_scankey_required(outkey);
  
             /*
              * We don't support RowCompare using equality; such a qual would
              * mess up the numberOfEqualCols tracking.
              */
             Assert(j != (BTEqualStrategyNumber - 1));
             continue;
         }
  
         /* have we seen one of these before? */
         if (xform[j] == NULL)
         {
             /* nope, so remember this scankey */
             xform[j] = cur;
         }
         else
         {
             /* yup, keep only the more restrictive key */
             if (_bt_compare_scankey_args(scan, cur, cur, xform[j],
                                          &test_result))
             {
                 if (test_result)
                     xform[j] = cur;
                 else if (j == (BTEqualStrategyNumber - 1))
                 {
                     /* key == a && key == b, but a != b */
                     so->qual_ok = false;
                     return;
                 }
                 /* else old key is more restrictive, keep it */
             }
             else
             {
                 /*
                  * We can't determine which key is more restrictive.  Keep the
                  * previous one in xform[j] and push this one directly to the
                  * output array.
                  */
                 ScanKey     outkey = &outkeys[new_numberOfKeys++];
  
                 memcpy(outkey, cur, sizeof(ScanKeyData));
                 if (numberOfEqualCols == attno - 1)
                     _bt_mark_scankey_required(outkey);
             }
         }
     }
  
     so->numberOfKeys = new_numberOfKeys;
 }

References _bt_compare_scankey_args(), _bt_fix_scankey_strategy(), _bt_mark_scankey_required(), BTScanOpaqueData::arrayKeyData, Assert(), BTEqualStrategyNumber, BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, BTMaxStrategyNumber, cur, elog(), ERROR, i, if(), IndexScanDescData::indexRelation, j, BTScanOpaqueData::keyData, IndexScanDescData::keyData, BTScanOpaqueData::numberOfKeys, IndexScanDescData::numberOfKeys, IndexScanDescData::opaque, BTScanOpaqueData::qual_ok, RelationData::rd_indoption, ScanKeyData::sk_flags, SK_ROW_HEADER, and SK_SEARCHNULL.

Referenced by _bt_first(), and _bt_restore_array_keys().

◆ _bt_restore_array_keys()

void _bt_restore_array_keys ( IndexScanDesc scan )

Definition at line 629 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     bool        changed = false;
     int         i;
  
     /* Restore each array key to its position when the mark was set */
     for (i = 0; i < so->numArrayKeys; i++)
     {
         BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
         ScanKey     skey = &so->arrayKeyData[curArrayKey->scan_key];
         int         mark_elem = curArrayKey->mark_elem;
  
         if (curArrayKey->cur_elem != mark_elem)
         {
             curArrayKey->cur_elem = mark_elem;
             skey->sk_argument = curArrayKey->elem_values[mark_elem];
             changed = true;
         }
     }
  
     /*
      * If we changed any keys, we must redo _bt_preprocess_keys.  That might
      * sound like overkill, but in cases with multiple keys per index column
      * it seems necessary to do the full set of pushups.
      */
     if (changed)
     {
         _bt_preprocess_keys(scan);
         /* The mark should have been set on a consistent set of keys... */
         Assert(so->qual_ok);
     }
 }

References _bt_preprocess_keys(), BTScanOpaqueData::arrayKeyData, BTScanOpaqueData::arrayKeys, Assert(), BTArrayKeyInfo::cur_elem, BTArrayKeyInfo::elem_values, i, BTArrayKeyInfo::mark_elem, BTScanOpaqueData::numArrayKeys, IndexScanDescData::opaque, BTScanOpaqueData::qual_ok, BTArrayKeyInfo::scan_key, and ScanKeyData::sk_argument.

Referenced by btrestrpos().

◆ _bt_sort_array_elements()

static int _bt_sort_array_elements	(	IndexScanDesc	scan,
		ScanKey	skey,
		bool	reverse,
		Datum *	elems,
		int	nelems
	)

static

Definition at line 449 of file nbtutils.c.

 {
     Relation    rel = scan->indexRelation;
     Oid         elemtype;
     RegProcedure cmp_proc;
     BTSortArrayContext cxt;
  
     if (nelems <= 1)
         return nelems;          /* no work to do */
  
     /*
      * Determine the nominal datatype of the array elements.  We have to
      * support the convention that sk_subtype == InvalidOid means the opclass
      * input type; this is a hack to simplify life for ScanKeyInit().
      */
     elemtype = skey->sk_subtype;
     if (elemtype == InvalidOid)
         elemtype = rel->rd_opcintype[skey->sk_attno - 1];
  
     /*
      * Look up the appropriate comparison function in the opfamily.
      *
      * Note: it's possible that this would fail, if the opfamily is
      * incomplete, but it seems quite unlikely that an opfamily would omit
      * non-cross-type support functions for any datatype that it supports at
      * all.
      */
     cmp_proc = get_opfamily_proc(rel->rd_opfamily[skey->sk_attno - 1],
                                  elemtype,
                                  elemtype,
                                  BTORDER_PROC);
     if (!RegProcedureIsValid(cmp_proc))
         elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
              BTORDER_PROC, elemtype, elemtype,
              rel->rd_opfamily[skey->sk_attno - 1]);
  
     /* Sort the array elements */
     fmgr_info(cmp_proc, &cxt.flinfo);
     cxt.collation = skey->sk_collation;
     cxt.reverse = reverse;
     qsort_arg((void *) elems, nelems, sizeof(Datum),
               _bt_compare_array_elements, (void *) &cxt);
  
     /* Now scan the sorted elements and remove duplicates */
     return qunique_arg(elems, nelems, sizeof(Datum),
                        _bt_compare_array_elements, &cxt);
 }

References _bt_compare_array_elements(), BTORDER_PROC, BTSortArrayContext::collation, elog(), ERROR, BTSortArrayContext::flinfo, fmgr_info(), get_opfamily_proc(), IndexScanDescData::indexRelation, InvalidOid, qsort_arg(), qunique_arg(), RelationData::rd_opcintype, RelationData::rd_opfamily, RegProcedureIsValid, BTSortArrayContext::reverse, ScanKeyData::sk_attno, ScanKeyData::sk_collation, and ScanKeyData::sk_subtype.

Referenced by _bt_preprocess_array_keys().

◆ _bt_start_array_keys()

void _bt_start_array_keys	(	IndexScanDesc	scan,
		ScanDirection	dir
	)

Definition at line 525 of file nbtutils.c.

 {
     BTScanOpaque so = (BTScanOpaque) scan->opaque;
     int         i;
  
     for (i = 0; i < so->numArrayKeys; i++)
     {
         BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
         ScanKey     skey = &so->arrayKeyData[curArrayKey->scan_key];
  
         Assert(curArrayKey->num_elems > 0);
         if (ScanDirectionIsBackward(dir))
             curArrayKey->cur_elem = curArrayKey->num_elems - 1;
         else
             curArrayKey->cur_elem = 0;
         skey->sk_argument = curArrayKey->elem_values[curArrayKey->cur_elem];
     }
 }

References BTScanOpaqueData::arrayKeyData, BTScanOpaqueData::arrayKeys, Assert(), BTArrayKeyInfo::cur_elem, BTArrayKeyInfo::elem_values, i, BTArrayKeyInfo::num_elems, BTScanOpaqueData::numArrayKeys, IndexScanDescData::opaque, BTArrayKeyInfo::scan_key, ScanDirectionIsBackward, and ScanKeyData::sk_argument.

Referenced by btgetbitmap(), and btgettuple().

◆ _bt_start_vacuum()

BTCycleId _bt_start_vacuum ( Relation rel )

Definition at line 1976 of file nbtutils.c.

 {
     BTCycleId   result;
     int         i;
     BTOneVacInfo *vac;
  
     LWLockAcquire(BtreeVacuumLock, LW_EXCLUSIVE);
  
     /*
      * Assign the next cycle ID, being careful to avoid zero as well as the
      * reserved high values.
      */
     result = ++(btvacinfo->cycle_ctr);
     if (result == 0 || result > MAX_BT_CYCLE_ID)
         result = btvacinfo->cycle_ctr = 1;
  
     /* Let's just make sure there's no entry already for this index */
     for (i = 0; i < btvacinfo->num_vacuums; i++)
     {
         vac = &btvacinfo->vacuums[i];
         if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
             vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
         {
             /*
              * Unlike most places in the backend, we have to explicitly
              * release our LWLock before throwing an error.  This is because
              * we expect _bt_end_vacuum() to be called before transaction
              * abort cleanup can run to release LWLocks.
              */
             LWLockRelease(BtreeVacuumLock);
             elog(ERROR, "multiple active vacuums for index \"%s\"",
                  RelationGetRelationName(rel));
         }
     }
  
     /* OK, add an entry */
     if (btvacinfo->num_vacuums >= btvacinfo->max_vacuums)
     {
         LWLockRelease(BtreeVacuumLock);
         elog(ERROR, "out of btvacinfo slots");
     }
     vac = &btvacinfo->vacuums[btvacinfo->num_vacuums];
     vac->relid = rel->rd_lockInfo.lockRelId;
     vac->cycleid = result;
     btvacinfo->num_vacuums++;
  
     LWLockRelease(BtreeVacuumLock);
     return result;
 }

References btvacinfo, BTVacInfo::cycle_ctr, BTOneVacInfo::cycleid, LockRelId::dbId, elog(), ERROR, i, LockInfoData::lockRelId, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), MAX_BT_CYCLE_ID, BTVacInfo::max_vacuums, BTVacInfo::num_vacuums, RelationData::rd_lockInfo, RelationGetRelationName, BTOneVacInfo::relid, LockRelId::relId, and BTVacInfo::vacuums.

Referenced by btbulkdelete().

◆ _bt_truncate()

IndexTuple _bt_truncate	(	Relation	rel,
		IndexTuple	lastleft,
		IndexTuple	firstright,
		BTScanInsert	itup_key
	)

Definition at line 2205 of file nbtutils.c.

 {
     TupleDesc   itupdesc = RelationGetDescr(rel);
     int16       nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
     int         keepnatts;
     IndexTuple  pivot;
     IndexTuple  tidpivot;
     ItemPointer pivotheaptid;
     Size        newsize;
  
     /*
      * We should only ever truncate non-pivot tuples from leaf pages.  It's
      * never okay to truncate when splitting an internal page.
      */
     Assert(!BTreeTupleIsPivot(lastleft) && !BTreeTupleIsPivot(firstright));
  
     /* Determine how many attributes must be kept in truncated tuple */
     keepnatts = _bt_keep_natts(rel, lastleft, firstright, itup_key);
  
 #ifdef DEBUG_NO_TRUNCATE
     /* Force truncation to be ineffective for testing purposes */
     keepnatts = nkeyatts + 1;
 #endif
  
     pivot = index_truncate_tuple(itupdesc, firstright,
                                  Min(keepnatts, nkeyatts));
  
     if (BTreeTupleIsPosting(pivot))
     {
         /*
          * index_truncate_tuple() just returns a straight copy of firstright
          * when it has no attributes to truncate.  When that happens, we may
          * need to truncate away a posting list here instead.
          */
         Assert(keepnatts == nkeyatts || keepnatts == nkeyatts + 1);
         Assert(IndexRelationGetNumberOfAttributes(rel) == nkeyatts);
         pivot->t_info &= ~INDEX_SIZE_MASK;
         pivot->t_info |= MAXALIGN(BTreeTupleGetPostingOffset(firstright));
     }
  
     /*
      * If there is a distinguishing key attribute within pivot tuple, we're
      * done
      */
     if (keepnatts <= nkeyatts)
     {
         BTreeTupleSetNAtts(pivot, keepnatts, false);
         return pivot;
     }
  
     /*
      * We have to store a heap TID in the new pivot tuple, since no non-TID
      * key attribute value in firstright distinguishes the right side of the
      * split from the left side.  nbtree conceptualizes this case as an
      * inability to truncate away any key attributes, since heap TID is
      * treated as just another key attribute (despite lacking a pg_attribute
      * entry).
      *
      * Use enlarged space that holds a copy of pivot.  We need the extra space
      * to store a heap TID at the end (using the special pivot tuple
      * representation).  Note that the original pivot already has firstright's
      * possible posting list/non-key attribute values removed at this point.
      */
     newsize = MAXALIGN(IndexTupleSize(pivot)) + MAXALIGN(sizeof(ItemPointerData));
     tidpivot = palloc0(newsize);
     memcpy(tidpivot, pivot, MAXALIGN(IndexTupleSize(pivot)));
     /* Cannot leak memory here */
     pfree(pivot);
  
     /*
      * Store all of firstright's key attribute values plus a tiebreaker heap
      * TID value in enlarged pivot tuple
      */
     tidpivot->t_info &= ~INDEX_SIZE_MASK;
     tidpivot->t_info |= newsize;
     BTreeTupleSetNAtts(tidpivot, nkeyatts, true);
     pivotheaptid = BTreeTupleGetHeapTID(tidpivot);
  
     /*
      * Lehman & Yao use lastleft as the leaf high key in all cases, but don't
      * consider suffix truncation.  It seems like a good idea to follow that
      * example in cases where no truncation takes place -- use lastleft's heap
      * TID.  (This is also the closest value to negative infinity that's
      * legally usable.)
      */
     ItemPointerCopy(BTreeTupleGetMaxHeapTID(lastleft), pivotheaptid);
  
     /*
      * We're done.  Assert() that heap TID invariants hold before returning.
      *
      * Lehman and Yao require that the downlink to the right page, which is to
      * be inserted into the parent page in the second phase of a page split be
      * a strict lower bound on items on the right page, and a non-strict upper
      * bound for items on the left page.  Assert that heap TIDs follow these
      * invariants, since a heap TID value is apparently needed as a
      * tiebreaker.
      */
 #ifndef DEBUG_NO_TRUNCATE
     Assert(ItemPointerCompare(BTreeTupleGetMaxHeapTID(lastleft),
                               BTreeTupleGetHeapTID(firstright)) < 0);
     Assert(ItemPointerCompare(pivotheaptid,
                               BTreeTupleGetHeapTID(lastleft)) >= 0);
     Assert(ItemPointerCompare(pivotheaptid,
                               BTreeTupleGetHeapTID(firstright)) < 0);
 #else
  
     /*
      * Those invariants aren't guaranteed to hold for lastleft + firstright
      * heap TID attribute values when they're considered here only because
      * DEBUG_NO_TRUNCATE is defined (a heap TID is probably not actually
      * needed as a tiebreaker).  DEBUG_NO_TRUNCATE must therefore use a heap
      * TID value that always works as a strict lower bound for items to the
      * right.  In particular, it must avoid using firstright's leading key
      * attribute values along with lastleft's heap TID value when lastleft's
      * TID happens to be greater than firstright's TID.
      */
     ItemPointerCopy(BTreeTupleGetHeapTID(firstright), pivotheaptid);
  
     /*
      * Pivot heap TID should never be fully equal to firstright.  Note that
      * the pivot heap TID will still end up equal to lastleft's heap TID when
      * that's the only usable value.
      */
     ItemPointerSetOffsetNumber(pivotheaptid,
                                OffsetNumberPrev(ItemPointerGetOffsetNumber(pivotheaptid)));
     Assert(ItemPointerCompare(pivotheaptid,
                               BTreeTupleGetHeapTID(firstright)) < 0);
 #endif
  
     return tidpivot;
 }

References _bt_keep_natts(), Assert(), BTreeTupleGetHeapTID(), BTreeTupleGetMaxHeapTID(), BTreeTupleGetPostingOffset(), BTreeTupleIsPivot(), BTreeTupleIsPosting(), BTreeTupleSetNAtts(), INDEX_SIZE_MASK, index_truncate_tuple(), IndexRelationGetNumberOfAttributes, IndexRelationGetNumberOfKeyAttributes, IndexTupleSize, ItemPointerCompare(), ItemPointerCopy(), ItemPointerGetOffsetNumber(), ItemPointerSetOffsetNumber(), MAXALIGN, Min, OffsetNumberPrev, palloc0(), pfree(), RelationGetDescr, and IndexTupleData::t_info.

Referenced by _bt_buildadd(), and _bt_split().

◆ _bt_vacuum_cycleid()

BTCycleId _bt_vacuum_cycleid ( Relation rel )

Definition at line 1942 of file nbtutils.c.

 {
     BTCycleId   result = 0;
     int         i;
  
     /* Share lock is enough since this is a read-only operation */
     LWLockAcquire(BtreeVacuumLock, LW_SHARED);
  
     for (i = 0; i < btvacinfo->num_vacuums; i++)
     {
         BTOneVacInfo *vac = &btvacinfo->vacuums[i];
  
         if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
             vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
         {
             result = vac->cycleid;
             break;
         }
     }
  
     LWLockRelease(BtreeVacuumLock);
     return result;
 }

References btvacinfo, BTOneVacInfo::cycleid, LockRelId::dbId, i, LockInfoData::lockRelId, LW_SHARED, LWLockAcquire(), LWLockRelease(), BTVacInfo::num_vacuums, RelationData::rd_lockInfo, BTOneVacInfo::relid, LockRelId::relId, and BTVacInfo::vacuums.

Referenced by _bt_split().

◆ btbuildphasename()

char* btbuildphasename ( int64 phasenum )

Definition at line 2157 of file nbtutils.c.

 {
     switch (phasenum)
     {
         case PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE:
             return "initializing";
         case PROGRESS_BTREE_PHASE_INDEXBUILD_TABLESCAN:
             return "scanning table";
         case PROGRESS_BTREE_PHASE_PERFORMSORT_1:
             return "sorting live tuples";
         case PROGRESS_BTREE_PHASE_PERFORMSORT_2:
             return "sorting dead tuples";
         case PROGRESS_BTREE_PHASE_LEAF_LOAD:
             return "loading tuples in tree";
         default:
             return NULL;
     }
 }

References PROGRESS_BTREE_PHASE_INDEXBUILD_TABLESCAN, PROGRESS_BTREE_PHASE_LEAF_LOAD, PROGRESS_BTREE_PHASE_PERFORMSORT_1, PROGRESS_BTREE_PHASE_PERFORMSORT_2, and PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE.

Referenced by bthandler().

◆ btoptions()

bytea* btoptions	(	Datum	reloptions,
		bool	validate
	)

Definition at line 2111 of file nbtutils.c.

 {
     static const relopt_parse_elt tab[] = {
         {"fillfactor", RELOPT_TYPE_INT, offsetof(BTOptions, fillfactor)},
         {"vacuum_cleanup_index_scale_factor", RELOPT_TYPE_REAL,
         offsetof(BTOptions, vacuum_cleanup_index_scale_factor)},
         {"deduplicate_items", RELOPT_TYPE_BOOL,
         offsetof(BTOptions, deduplicate_items)}
     };
  
     return (bytea *) build_reloptions(reloptions, validate,
                                       RELOPT_KIND_BTREE,
                                       sizeof(BTOptions),
                                       tab, lengthof(tab));
 }

References build_reloptions(), fillfactor, lengthof, RELOPT_KIND_BTREE, RELOPT_TYPE_BOOL, RELOPT_TYPE_INT, and RELOPT_TYPE_REAL.

Referenced by bthandler().

◆ btproperty()

bool btproperty	(	Oid	index_oid,
		int	attno,
		IndexAMProperty	prop,
		const char *	propname,
		bool *	res,
		bool *	isnull
	)

Definition at line 2134 of file nbtutils.c.

 {
     switch (prop)
     {
         case AMPROP_RETURNABLE:
             /* answer only for columns, not AM or whole index */
             if (attno == 0)
                 return false;
             /* otherwise, btree can always return data */
             *res = true;
             return true;
  
         default:
             return false;       /* punt to generic code */
     }
 }

References AMPROP_RETURNABLE, and res.

Referenced by bthandler().

◆ BTreeShmemInit()

void BTreeShmemInit ( void )

Definition at line 2083 of file nbtutils.c.

 {
     bool        found;
  
     btvacinfo = (BTVacInfo *) ShmemInitStruct("BTree Vacuum State",
                                               BTreeShmemSize(),
                                               &found);
  
     if (!IsUnderPostmaster)
     {
         /* Initialize shared memory area */
         Assert(!found);
  
         /*
          * It doesn't really matter what the cycle counter starts at, but
          * having it always start the same doesn't seem good.  Seed with
          * low-order bits of time() instead.
          */
         btvacinfo->cycle_ctr = (BTCycleId) time(NULL);
  
         btvacinfo->num_vacuums = 0;
         btvacinfo->max_vacuums = MaxBackends;
     }
     else
         Assert(found);
 }

References Assert(), BTreeShmemSize(), btvacinfo, BTVacInfo::cycle_ctr, IsUnderPostmaster, BTVacInfo::max_vacuums, MaxBackends, BTVacInfo::num_vacuums, and ShmemInitStruct().

Referenced by CreateSharedMemoryAndSemaphores().

◆ BTreeShmemSize()

Size BTreeShmemSize ( void )

Definition at line 2070 of file nbtutils.c.

 {
     Size        size;
  
     size = offsetof(BTVacInfo, vacuums);
     size = add_size(size, mul_size(MaxBackends, sizeof(BTOneVacInfo)));
     return size;
 }

References add_size(), MaxBackends, and mul_size().

Referenced by BTreeShmemInit(), and CalculateShmemSize().

Variable Documentation

◆ btvacinfo

BTVacInfo* btvacinfo

static

Definition at line 1929 of file nbtutils.c.

Referenced by _bt_end_vacuum(), _bt_start_vacuum(), _bt_vacuum_cycleid(), and BTreeShmemInit().

Data Structures

Typedefs

Functions

Variables

Typedef Documentation

◆ BTOneVacInfo

◆ BTSortArrayContext

◆ BTVacInfo

Function Documentation

◆ _bt_advance_array_keys()

◆ _bt_allequalimage()

◆ _bt_check_natts()

◆ _bt_check_rowcompare()

◆ _bt_check_third_page()

◆ _bt_checkkeys()

◆ _bt_compare_array_elements()

◆ _bt_compare_scankey_args()

◆ _bt_end_vacuum()

◆ _bt_end_vacuum_callback()

◆ _bt_find_extreme_element()

◆ _bt_fix_scankey_strategy()

◆ _bt_freestack()

◆ _bt_keep_natts()

◆ _bt_keep_natts_fast()

◆ _bt_killitems()

◆ _bt_mark_array_keys()

◆ _bt_mark_scankey_required()

◆ _bt_mkscankey()

◆ _bt_preprocess_array_keys()

◆ _bt_preprocess_keys()

◆ _bt_restore_array_keys()

◆ _bt_sort_array_elements()

◆ _bt_start_array_keys()

◆ _bt_start_vacuum()

◆ _bt_truncate()

◆ _bt_vacuum_cycleid()

◆ btbuildphasename()

◆ btoptions()

◆ btproperty()

◆ BTreeShmemInit()

◆ BTreeShmemSize()

Variable Documentation

◆ btvacinfo