#include "postgres.h"
#include "access/hash.h"
#include "access/htup_details.h"
#include "access/nbtree.h"
#include "access/relation.h"
#include "catalog/partition.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_partitioned_table.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/optimizer.h"
#include "partitioning/partbounds.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/partcache.h"
#include "utils/rel.h"
#include "utils/syscache.h"

Include dependency graph for partcache.c:

Functions
static void	RelationBuildPartitionKey (Relation relation)

static List *	generate_partition_qual (Relation rel)

PartitionKey	RelationGetPartitionKey (Relation rel)

List *	RelationGetPartitionQual (Relation rel)

Expr *	get_partition_qual_relid (Oid relid)

Function Documentation

◆ generate_partition_qual()

static List * generate_partition_qual ( Relation rel )

static

Definition at line 337 of file partcache.c.

 {
     HeapTuple   tuple;
     MemoryContext oldcxt;
     Datum       boundDatum;
     bool        isnull;
     List       *my_qual = NIL,
                *result = NIL;
     Oid         parentrelid;
     Relation    parent;
  
     /* Guard against stack overflow due to overly deep partition tree */
     check_stack_depth();
  
     /* If we already cached the result, just return a copy */
     if (rel->rd_partcheckvalid)
         return copyObject(rel->rd_partcheck);
  
     /*
      * Grab at least an AccessShareLock on the parent table.  Must do this
      * even if the partition has been partially detached, because transactions
      * concurrent with the detach might still be trying to use a partition
      * descriptor that includes it.
      */
     parentrelid = get_partition_parent(RelationGetRelid(rel), true);
     parent = relation_open(parentrelid, AccessShareLock);
  
     /* Get pg_class.relpartbound */
     tuple = SearchSysCache1(RELOID,
                             ObjectIdGetDatum(RelationGetRelid(rel)));
     if (!HeapTupleIsValid(tuple))
         elog(ERROR, "cache lookup failed for relation %u",
              RelationGetRelid(rel));
  
     boundDatum = SysCacheGetAttr(RELOID, tuple,
                                  Anum_pg_class_relpartbound,
                                  &isnull);
     if (!isnull)
     {
         PartitionBoundSpec *bound;
  
         bound = castNode(PartitionBoundSpec,
                          stringToNode(TextDatumGetCString(boundDatum)));
  
         my_qual = get_qual_from_partbound(parent, bound);
     }
  
     ReleaseSysCache(tuple);
  
     /* Add the parent's quals to the list (if any) */
     if (parent->rd_rel->relispartition)
         result = list_concat(generate_partition_qual(parent), my_qual);
     else
         result = my_qual;
  
     /*
      * Change Vars to have partition's attnos instead of the parent's. We do
      * this after we concatenate the parent's quals, because we want every Var
      * in it to bear this relation's attnos. It's safe to assume varno = 1
      * here.
      */
     result = map_partition_varattnos(result, 1, rel, parent);
  
     /* Assert that we're not leaking any old data during assignments below */
     Assert(rel->rd_partcheckcxt == NULL);
     Assert(rel->rd_partcheck == NIL);
  
     /*
      * Save a copy in the relcache.  The order of these operations is fairly
      * critical to avoid memory leaks and ensure that we don't leave a corrupt
      * relcache entry if we fail partway through copyObject.
      *
      * If, as is definitely possible, the partcheck list is NIL, then we do
      * not need to make a context to hold it.
      */
     if (result != NIL)
     {
         rel->rd_partcheckcxt = AllocSetContextCreate(CacheMemoryContext,
                                                      "partition constraint",
                                                      ALLOCSET_SMALL_SIZES);
         MemoryContextCopyAndSetIdentifier(rel->rd_partcheckcxt,
                                           RelationGetRelationName(rel));
         oldcxt = MemoryContextSwitchTo(rel->rd_partcheckcxt);
         rel->rd_partcheck = copyObject(result);
         MemoryContextSwitchTo(oldcxt);
     }
     else
         rel->rd_partcheck = NIL;
     rel->rd_partcheckvalid = true;
  
     /* Keep the parent locked until commit */
     relation_close(parent, NoLock);
  
     /* Return the working copy to the caller */
     return result;
 }

References AccessShareLock, ALLOCSET_SMALL_SIZES, AllocSetContextCreate, Assert, CacheMemoryContext, castNode, check_stack_depth(), copyObject, elog, ERROR, get_partition_parent(), get_qual_from_partbound(), HeapTupleIsValid, list_concat(), map_partition_varattnos(), MemoryContextCopyAndSetIdentifier, MemoryContextSwitchTo(), NIL, NoLock, ObjectIdGetDatum(), RelationData::rd_partcheck, RelationData::rd_partcheckcxt, RelationData::rd_partcheckvalid, RelationData::rd_rel, relation_close(), relation_open(), RelationGetRelationName, RelationGetRelid, ReleaseSysCache(), SearchSysCache1(), stringToNode(), SysCacheGetAttr(), and TextDatumGetCString.

Referenced by get_partition_qual_relid(), and RelationGetPartitionQual().

◆ get_partition_qual_relid()

Expr* get_partition_qual_relid ( Oid relid )

Definition at line 299 of file partcache.c.

 {
     Expr       *result = NULL;
  
     /* Do the work only if this relation exists and is a partition. */
     if (get_rel_relispartition(relid))
     {
         Relation    rel = relation_open(relid, AccessShareLock);
         List       *and_args;
  
         and_args = generate_partition_qual(rel);
  
         /* Convert implicit-AND list format to boolean expression */
         if (and_args == NIL)
             result = NULL;
         else if (list_length(and_args) > 1)
             result = makeBoolExpr(AND_EXPR, and_args, -1);
         else
             result = linitial(and_args);
  
         /* Keep the lock, to allow safe deparsing against the rel by caller. */
         relation_close(rel, NoLock);
     }
  
     return result;
 }

References AccessShareLock, AND_EXPR, generate_partition_qual(), get_rel_relispartition(), linitial, list_length(), makeBoolExpr(), NIL, NoLock, relation_close(), and relation_open().

Referenced by pg_get_partconstrdef_string(), and pg_get_partition_constraintdef().

◆ RelationBuildPartitionKey()

static void RelationBuildPartitionKey ( Relation relation )

static

Definition at line 78 of file partcache.c.

 {
     Form_pg_partitioned_table form;
     HeapTuple   tuple;
     bool        isnull;
     int         i;
     PartitionKey key;
     AttrNumber *attrs;
     oidvector  *opclass;
     oidvector  *collation;
     ListCell   *partexprs_item;
     Datum       datum;
     MemoryContext partkeycxt,
                 oldcxt;
     int16       procnum;
  
     tuple = SearchSysCache1(PARTRELID,
                             ObjectIdGetDatum(RelationGetRelid(relation)));
  
     if (!HeapTupleIsValid(tuple))
         elog(ERROR, "cache lookup failed for partition key of relation %u",
              RelationGetRelid(relation));
  
     partkeycxt = AllocSetContextCreate(CurTransactionContext,
                                        "partition key",
                                        ALLOCSET_SMALL_SIZES);
     MemoryContextCopyAndSetIdentifier(partkeycxt,
                                       RelationGetRelationName(relation));
  
     key = (PartitionKey) MemoryContextAllocZero(partkeycxt,
                                                 sizeof(PartitionKeyData));
  
     /* Fixed-length attributes */
     form = (Form_pg_partitioned_table) GETSTRUCT(tuple);
     key->strategy = form->partstrat;
     key->partnatts = form->partnatts;
  
     /* Validate partition strategy code */
     if (key->strategy != PARTITION_STRATEGY_LIST &&
         key->strategy != PARTITION_STRATEGY_RANGE &&
         key->strategy != PARTITION_STRATEGY_HASH)
         elog(ERROR, "invalid partition strategy \"%c\"", key->strategy);
  
     /*
      * We can rely on the first variable-length attribute being mapped to the
      * relevant field of the catalog's C struct, because all previous
      * attributes are non-nullable and fixed-length.
      */
     attrs = form->partattrs.values;
  
     /* But use the hard way to retrieve further variable-length attributes */
     /* Operator class */
     datum = SysCacheGetAttrNotNull(PARTRELID, tuple,
                                    Anum_pg_partitioned_table_partclass);
     opclass = (oidvector *) DatumGetPointer(datum);
  
     /* Collation */
     datum = SysCacheGetAttrNotNull(PARTRELID, tuple,
                                    Anum_pg_partitioned_table_partcollation);
     collation = (oidvector *) DatumGetPointer(datum);
  
     /* Expressions */
     datum = SysCacheGetAttr(PARTRELID, tuple,
                             Anum_pg_partitioned_table_partexprs, &isnull);
     if (!isnull)
     {
         char       *exprString;
         Node       *expr;
  
         exprString = TextDatumGetCString(datum);
         expr = stringToNode(exprString);
         pfree(exprString);
  
         /*
          * Run the expressions through const-simplification since the planner
          * will be comparing them to similarly-processed qual clause operands,
          * and may fail to detect valid matches without this step; fix
          * opfuncids while at it.  We don't need to bother with
          * canonicalize_qual() though, because partition expressions should be
          * in canonical form already (ie, no need for OR-merging or constant
          * elimination).
          */
         expr = eval_const_expressions(NULL, expr);
         fix_opfuncids(expr);
  
         oldcxt = MemoryContextSwitchTo(partkeycxt);
         key->partexprs = (List *) copyObject(expr);
         MemoryContextSwitchTo(oldcxt);
     }
  
     /* Allocate assorted arrays in the partkeycxt, which we'll fill below */
     oldcxt = MemoryContextSwitchTo(partkeycxt);
     key->partattrs = (AttrNumber *) palloc0(key->partnatts * sizeof(AttrNumber));
     key->partopfamily = (Oid *) palloc0(key->partnatts * sizeof(Oid));
     key->partopcintype = (Oid *) palloc0(key->partnatts * sizeof(Oid));
     key->partsupfunc = (FmgrInfo *) palloc0(key->partnatts * sizeof(FmgrInfo));
  
     key->partcollation = (Oid *) palloc0(key->partnatts * sizeof(Oid));
     key->parttypid = (Oid *) palloc0(key->partnatts * sizeof(Oid));
     key->parttypmod = (int32 *) palloc0(key->partnatts * sizeof(int32));
     key->parttyplen = (int16 *) palloc0(key->partnatts * sizeof(int16));
     key->parttypbyval = (bool *) palloc0(key->partnatts * sizeof(bool));
     key->parttypalign = (char *) palloc0(key->partnatts * sizeof(char));
     key->parttypcoll = (Oid *) palloc0(key->partnatts * sizeof(Oid));
     MemoryContextSwitchTo(oldcxt);
  
     /* determine support function number to search for */
     procnum = (key->strategy == PARTITION_STRATEGY_HASH) ?
         HASHEXTENDED_PROC : BTORDER_PROC;
  
     /* Copy partattrs and fill other per-attribute info */
     memcpy(key->partattrs, attrs, key->partnatts * sizeof(int16));
     partexprs_item = list_head(key->partexprs);
     for (i = 0; i < key->partnatts; i++)
     {
         AttrNumber  attno = key->partattrs[i];
         HeapTuple   opclasstup;
         Form_pg_opclass opclassform;
         Oid         funcid;
  
         /* Collect opfamily information */
         opclasstup = SearchSysCache1(CLAOID,
                                      ObjectIdGetDatum(opclass->values[i]));
         if (!HeapTupleIsValid(opclasstup))
             elog(ERROR, "cache lookup failed for opclass %u", opclass->values[i]);
  
         opclassform = (Form_pg_opclass) GETSTRUCT(opclasstup);
         key->partopfamily[i] = opclassform->opcfamily;
         key->partopcintype[i] = opclassform->opcintype;
  
         /* Get a support function for the specified opfamily and datatypes */
         funcid = get_opfamily_proc(opclassform->opcfamily,
                                    opclassform->opcintype,
                                    opclassform->opcintype,
                                    procnum);
         if (!OidIsValid(funcid))
             ereport(ERROR,
                     (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                      errmsg("operator class \"%s\" of access method %s is missing support function %d for type %s",
                             NameStr(opclassform->opcname),
                             (key->strategy == PARTITION_STRATEGY_HASH) ?
                             "hash" : "btree",
                             procnum,
                             format_type_be(opclassform->opcintype))));
  
         fmgr_info_cxt(funcid, &key->partsupfunc[i], partkeycxt);
  
         /* Collation */
         key->partcollation[i] = collation->values[i];
  
         /* Collect type information */
         if (attno != 0)
         {
             Form_pg_attribute att = TupleDescAttr(relation->rd_att, attno - 1);
  
             key->parttypid[i] = att->atttypid;
             key->parttypmod[i] = att->atttypmod;
             key->parttypcoll[i] = att->attcollation;
         }
         else
         {
             if (partexprs_item == NULL)
                 elog(ERROR, "wrong number of partition key expressions");
  
             key->parttypid[i] = exprType(lfirst(partexprs_item));
             key->parttypmod[i] = exprTypmod(lfirst(partexprs_item));
             key->parttypcoll[i] = exprCollation(lfirst(partexprs_item));
  
             partexprs_item = lnext(key->partexprs, partexprs_item);
         }
         get_typlenbyvalalign(key->parttypid[i],
                              &key->parttyplen[i],
                              &key->parttypbyval[i],
                              &key->parttypalign[i]);
  
         ReleaseSysCache(opclasstup);
     }
  
     ReleaseSysCache(tuple);
  
     /* Assert that we're not leaking any old data during assignments below */
     Assert(relation->rd_partkeycxt == NULL);
     Assert(relation->rd_partkey == NULL);
  
     /*
      * Success --- reparent our context and make the relcache point to the
      * newly constructed key
      */
     MemoryContextSetParent(partkeycxt, CacheMemoryContext);
     relation->rd_partkeycxt = partkeycxt;
     relation->rd_partkey = key;
 }

References ALLOCSET_SMALL_SIZES, AllocSetContextCreate, Assert, BTORDER_PROC, CacheMemoryContext, copyObject, CurTransactionContext, DatumGetPointer(), elog, ereport, errcode(), errmsg(), ERROR, eval_const_expressions(), exprCollation(), exprType(), exprTypmod(), fix_opfuncids(), fmgr_info_cxt(), format_type_be(), get_opfamily_proc(), get_typlenbyvalalign(), GETSTRUCT, HASHEXTENDED_PROC, HeapTupleIsValid, i, sort-test::key, lfirst, list_head(), lnext(), MemoryContextAllocZero(), MemoryContextCopyAndSetIdentifier, MemoryContextSetParent(), MemoryContextSwitchTo(), NameStr, ObjectIdGetDatum(), OidIsValid, palloc0(), PARTITION_STRATEGY_HASH, PARTITION_STRATEGY_LIST, PARTITION_STRATEGY_RANGE, pfree(), RelationData::rd_att, RelationData::rd_partkey, RelationData::rd_partkeycxt, RelationGetRelationName, RelationGetRelid, ReleaseSysCache(), SearchSysCache1(), stringToNode(), SysCacheGetAttr(), SysCacheGetAttrNotNull(), TextDatumGetCString, TupleDescAttr, and oidvector::values.

Referenced by RelationGetPartitionKey().

◆ RelationGetPartitionKey()

PartitionKey RelationGetPartitionKey ( Relation rel )

Definition at line 51 of file partcache.c.

 {
     if (rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
         return NULL;
  
     if (unlikely(rel->rd_partkey == NULL))
         RelationBuildPartitionKey(rel);
  
     return rel->rd_partkey;
 }

References RelationData::rd_partkey, RelationData::rd_rel, RelationBuildPartitionKey(), and unlikely.

Referenced by check_new_partition_bound(), CreatePartitionPruneState(), DefineIndex(), ExecBuildSlotPartitionKeyDescription(), ExecInitPartitionDispatchInfo(), find_partition_scheme(), get_qual_for_hash(), get_qual_for_list(), get_qual_for_range(), get_qual_from_partbound(), has_partition_attrs(), RelationBuildPartitionDesc(), satisfies_hash_partition(), set_baserel_partition_key_exprs(), transformPartitionBound(), transformPartitionCmd(), and transformPartitionRangeBounds().

◆ RelationGetPartitionQual()

List* RelationGetPartitionQual ( Relation rel )

Definition at line 277 of file partcache.c.

 {
     /* Quick exit */
     if (!rel->rd_rel->relispartition)
         return NIL;
  
     return generate_partition_qual(rel);
 }

References generate_partition_qual(), NIL, and RelationData::rd_rel.