PostgreSQL Source Code  git master
hstore_gin.c
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1 /*
2  * contrib/hstore/hstore_gin.c
3  */
4 #include "postgres.h"
5 
6 #include "access/gin.h"
7 #include "access/stratnum.h"
8 #include "catalog/pg_type.h"
9 
10 #include "hstore.h"
11 
12 
13 /*
14  * When using a GIN index for hstore, we choose to index both keys and values.
15  * The storage format is "text" values, with K, V, or N prepended to the string
16  * to indicate key, value, or null values. (As of 9.1 it might be better to
17  * store null values as nulls, but we'll keep it this way for on-disk
18  * compatibility.)
19  */
20 #define KEYFLAG 'K'
21 #define VALFLAG 'V'
22 #define NULLFLAG 'N'
23 
25 
26 /* Build an indexable text value */
27 static text *
28 makeitem(char *str, int len, char flag)
29 {
30  text *item;
31 
32  item = (text *) palloc(VARHDRSZ + len + 1);
33  SET_VARSIZE(item, VARHDRSZ + len + 1);
34 
35  *VARDATA(item) = flag;
36 
37  if (str && len > 0)
38  memcpy(VARDATA(item) + 1, str, len);
39 
40  return item;
41 }
42 
43 Datum
45 {
46  HStore *hs = PG_GETARG_HSTORE_P(0);
47  int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
48  Datum *entries = NULL;
49  HEntry *hsent = ARRPTR(hs);
50  char *ptr = STRPTR(hs);
51  int count = HS_COUNT(hs);
52  int i;
53 
54  *nentries = 2 * count;
55  if (count)
56  entries = (Datum *) palloc(sizeof(Datum) * 2 * count);
57 
58  for (i = 0; i < count; ++i)
59  {
60  text *item;
61 
62  item = makeitem(HSTORE_KEY(hsent, ptr, i),
63  HSTORE_KEYLEN(hsent, i),
64  KEYFLAG);
65  entries[2 * i] = PointerGetDatum(item);
66 
67  if (HSTORE_VALISNULL(hsent, i))
68  item = makeitem(NULL, 0, NULLFLAG);
69  else
70  item = makeitem(HSTORE_VAL(hsent, ptr, i),
71  HSTORE_VALLEN(hsent, i),
72  VALFLAG);
73  entries[2 * i + 1] = PointerGetDatum(item);
74  }
75 
76  PG_RETURN_POINTER(entries);
77 }
78 
80 
81 Datum
83 {
84  int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
85  StrategyNumber strategy = PG_GETARG_UINT16(2);
86  int32 *searchMode = (int32 *) PG_GETARG_POINTER(6);
87  Datum *entries;
88 
89  if (strategy == HStoreContainsStrategyNumber)
90  {
91  /* Query is an hstore, so just apply gin_extract_hstore... */
92  entries = (Datum *)
94  PG_GETARG_DATUM(0),
95  PointerGetDatum(nentries)));
96  /* ... except that "contains {}" requires a full index scan */
97  if (entries == NULL)
98  *searchMode = GIN_SEARCH_MODE_ALL;
99  }
100  else if (strategy == HStoreExistsStrategyNumber)
101  {
102  text *query = PG_GETARG_TEXT_PP(0);
103  text *item;
104 
105  *nentries = 1;
106  entries = (Datum *) palloc(sizeof(Datum));
107  item = makeitem(VARDATA_ANY(query), VARSIZE_ANY_EXHDR(query), KEYFLAG);
108  entries[0] = PointerGetDatum(item);
109  }
110  else if (strategy == HStoreExistsAnyStrategyNumber ||
111  strategy == HStoreExistsAllStrategyNumber)
112  {
113  ArrayType *query = PG_GETARG_ARRAYTYPE_P(0);
114  Datum *key_datums;
115  bool *key_nulls;
116  int key_count;
117  int i,
118  j;
119  text *item;
120 
121  deconstruct_array_builtin(query, TEXTOID, &key_datums, &key_nulls, &key_count);
122 
123  entries = (Datum *) palloc(sizeof(Datum) * key_count);
124 
125  for (i = 0, j = 0; i < key_count; ++i)
126  {
127  /* Nulls in the array are ignored, cf hstoreArrayToPairs */
128  if (key_nulls[i])
129  continue;
130  item = makeitem(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ, KEYFLAG);
131  entries[j++] = PointerGetDatum(item);
132  }
133 
134  *nentries = j;
135  /* ExistsAll with no keys should match everything */
136  if (j == 0 && strategy == HStoreExistsAllStrategyNumber)
137  *searchMode = GIN_SEARCH_MODE_ALL;
138  }
139  else
140  {
141  elog(ERROR, "unrecognized strategy number: %d", strategy);
142  entries = NULL; /* keep compiler quiet */
143  }
144 
145  PG_RETURN_POINTER(entries);
146 }
147 
149 
150 Datum
152 {
153  bool *check = (bool *) PG_GETARG_POINTER(0);
154  StrategyNumber strategy = PG_GETARG_UINT16(1);
155 
156  /* HStore *query = PG_GETARG_HSTORE_P(2); */
157  int32 nkeys = PG_GETARG_INT32(3);
158 
159  /* Pointer *extra_data = (Pointer *) PG_GETARG_POINTER(4); */
160  bool *recheck = (bool *) PG_GETARG_POINTER(5);
161  bool res = true;
162  int32 i;
163 
164  if (strategy == HStoreContainsStrategyNumber)
165  {
166  /*
167  * Index doesn't have information about correspondence of keys and
168  * values, so we need recheck. However, if not all the keys are
169  * present, we can fail at once.
170  */
171  *recheck = true;
172  for (i = 0; i < nkeys; i++)
173  {
174  if (!check[i])
175  {
176  res = false;
177  break;
178  }
179  }
180  }
181  else if (strategy == HStoreExistsStrategyNumber)
182  {
183  /* Existence of key is guaranteed in default search mode */
184  *recheck = false;
185  res = true;
186  }
187  else if (strategy == HStoreExistsAnyStrategyNumber)
188  {
189  /* Existence of key is guaranteed in default search mode */
190  *recheck = false;
191  res = true;
192  }
193  else if (strategy == HStoreExistsAllStrategyNumber)
194  {
195  /* Testing for all the keys being present gives an exact result */
196  *recheck = false;
197  for (i = 0; i < nkeys; i++)
198  {
199  if (!check[i])
200  {
201  res = false;
202  break;
203  }
204  }
205  }
206  else
207  elog(ERROR, "unrecognized strategy number: %d", strategy);
208 
210 }
#define PG_GETARG_ARRAYTYPE_P(n)
Definition: array.h:256
void deconstruct_array_builtin(ArrayType *array, Oid elmtype, Datum **elemsp, bool **nullsp, int *nelemsp)
Definition: arrayfuncs.c:3642
signed int int32
Definition: c.h:430
#define VARHDRSZ
Definition: c.h:628
#define ARRPTR(x)
Definition: cube.c:25
#define ERROR
Definition: elog.h:35
#define PG_GETARG_TEXT_PP(n)
Definition: fmgr.h:309
#define DirectFunctionCall2(func, arg1, arg2)
Definition: fmgr.h:644
#define PG_GETARG_POINTER(n)
Definition: fmgr.h:276
#define PG_GETARG_DATUM(n)
Definition: fmgr.h:268
#define PG_GETARG_UINT16(n)
Definition: fmgr.h:272
#define PG_GETARG_INT32(n)
Definition: fmgr.h:269
#define PG_RETURN_POINTER(x)
Definition: fmgr.h:361
#define PG_FUNCTION_ARGS
Definition: fmgr.h:193
#define PG_RETURN_BOOL(x)
Definition: fmgr.h:359
#define GIN_SEARCH_MODE_ALL
Definition: gin.h:36
#define HStoreExistsAllStrategyNumber
Definition: hstore.h:183
#define HStoreExistsStrategyNumber
Definition: hstore.h:181
#define HS_COUNT(hsp_)
Definition: hstore.h:61
#define HSTORE_KEY(arr_, str_, i_)
Definition: hstore.h:79
#define PG_GETARG_HSTORE_P(x)
Definition: hstore.h:154
#define HStoreExistsAnyStrategyNumber
Definition: hstore.h:182
#define HStoreContainsStrategyNumber
Definition: hstore.h:180
#define HSTORE_VALISNULL(arr_, i_)
Definition: hstore.h:83
#define HSTORE_VALLEN(arr_, i_)
Definition: hstore.h:82
#define HSTORE_KEYLEN(arr_, i_)
Definition: hstore.h:81
#define HSTORE_VAL(arr_, str_, i_)
Definition: hstore.h:80
#define STRPTR(x)
Definition: hstore.h:76
#define VALFLAG
Definition: hstore_gin.c:21
Datum gin_consistent_hstore(PG_FUNCTION_ARGS)
Definition: hstore_gin.c:151
Datum gin_extract_hstore_query(PG_FUNCTION_ARGS)
Definition: hstore_gin.c:82
static text * makeitem(char *str, int len, char flag)
Definition: hstore_gin.c:28
PG_FUNCTION_INFO_V1(gin_extract_hstore)
#define NULLFLAG
Definition: hstore_gin.c:22
Datum gin_extract_hstore(PG_FUNCTION_ARGS)
Definition: hstore_gin.c:44
#define KEYFLAG
Definition: hstore_gin.c:20
int j
Definition: isn.c:74
int i
Definition: isn.c:73
void * palloc(Size size)
Definition: mcxt.c:1199
const void size_t len
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:670
uintptr_t Datum
Definition: postgres.h:412
#define VARDATA(PTR)
Definition: postgres.h:316
static Pointer DatumGetPointer(Datum X)
Definition: postgres.h:660
#define VARDATA_ANY(PTR)
Definition: postgres.h:362
#define SET_VARSIZE(PTR, len)
Definition: postgres.h:343
#define VARSIZE(PTR)
Definition: postgres.h:317
#define VARSIZE_ANY_EXHDR(PTR)
Definition: postgres.h:355
uint16 StrategyNumber
Definition: stratnum.h:22
Definition: hstore.h:19
Definition: hstore.h:45
Definition: c.h:623
char * flag(int b)
Definition: test-ctype.c:33