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attoptcache.h File Reference
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Data Structures

struct  AttributeOpts
 

Typedefs

typedef struct AttributeOpts AttributeOpts
 

Functions

AttributeOptsget_attribute_options (Oid spcid, int attnum)
 

Typedef Documentation

Function Documentation

AttributeOpts* get_attribute_options ( Oid  spcid,
int  attnum 
)

Definition at line 104 of file attoptcache.c.

References Anum_pg_attribute_attoptions, AttoptCacheKey::attnum, ATTNUM, AttoptCacheKey::attrelid, attribute_reloptions(), CacheMemoryContext, HASH_ENTER, HASH_FIND, hash_search(), HeapTupleIsValid, InitializeAttoptCache(), Int16GetDatum, MemoryContextAlloc(), NULL, ObjectIdGetDatum, AttoptCacheEntry::opts, palloc(), ReleaseSysCache(), result, SearchSysCache2, SysCacheGetAttr(), and VARSIZE.

Referenced by compute_index_stats(), and do_analyze_rel().

105 {
106  AttoptCacheKey key;
107  AttoptCacheEntry *attopt;
109  HeapTuple tp;
110 
111  /* Find existing cache entry, if any. */
112  if (!AttoptCacheHash)
114  memset(&key, 0, sizeof(key)); /* make sure any padding bits are unset */
115  key.attrelid = attrelid;
116  key.attnum = attnum;
117  attopt =
119  (void *) &key,
120  HASH_FIND,
121  NULL);
122 
123  /* Not found in Attopt cache. Construct new cache entry. */
124  if (!attopt)
125  {
126  AttributeOpts *opts;
127 
128  tp = SearchSysCache2(ATTNUM,
129  ObjectIdGetDatum(attrelid),
130  Int16GetDatum(attnum));
131 
132  /*
133  * If we don't find a valid HeapTuple, it must mean someone has
134  * managed to request attribute details for a non-existent attribute.
135  * We treat that case as if no options were specified.
136  */
137  if (!HeapTupleIsValid(tp))
138  opts = NULL;
139  else
140  {
141  Datum datum;
142  bool isNull;
143 
144  datum = SysCacheGetAttr(ATTNUM,
145  tp,
147  &isNull);
148  if (isNull)
149  opts = NULL;
150  else
151  {
152  bytea *bytea_opts = attribute_reloptions(datum, false);
153 
155  VARSIZE(bytea_opts));
156  memcpy(opts, bytea_opts, VARSIZE(bytea_opts));
157  }
158  ReleaseSysCache(tp);
159  }
160 
161  /*
162  * It's important to create the actual cache entry only after reading
163  * pg_attribute, since the read could cause a cache flush.
164  */
166  (void *) &key,
167  HASH_ENTER,
168  NULL);
169  attopt->opts = opts;
170  }
171 
172  /* Return results in caller's memory context. */
173  if (attopt->opts == NULL)
174  return NULL;
175  result = palloc(VARSIZE(attopt->opts));
176  memcpy(result, attopt->opts, VARSIZE(attopt->opts));
177  return result;
178 }
#define VARSIZE(PTR)
Definition: postgres.h:304
#define Int16GetDatum(X)
Definition: postgres.h:457
return result
Definition: formatting.c:1633
void * hash_search(HTAB *hashp, const void *keyPtr, HASHACTION action, bool *foundPtr)
Definition: dynahash.c:885
bytea * attribute_reloptions(Datum reloptions, bool validate)
Definition: reloptions.c:1462
#define ObjectIdGetDatum(X)
Definition: postgres.h:513
static HTAB * AttoptCacheHash
Definition: attoptcache.c:28
uintptr_t Datum
Definition: postgres.h:372
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:1117
Datum SysCacheGetAttr(int cacheId, HeapTuple tup, AttrNumber attributeNumber, bool *isNull)
Definition: syscache.c:1279
#define HeapTupleIsValid(tuple)
Definition: htup.h:77
#define NULL
Definition: c.h:229
AttributeOpts * opts
Definition: attoptcache.c:40
#define Anum_pg_attribute_attoptions
Definition: pg_attribute.h:215
void * palloc(Size size)
Definition: mcxt.c:849
void * MemoryContextAlloc(MemoryContext context, Size size)
Definition: mcxt.c:707
static void InitializeAttoptCache(void)
Definition: attoptcache.c:77
Definition: c.h:439
MemoryContext CacheMemoryContext
Definition: mcxt.c:46
#define SearchSysCache2(cacheId, key1, key2)
Definition: syscache.h:158