PostGIS  2.5.0beta1dev-r@@SVN_REVISION@@

◆ pg_get_nd_stats()

static ND_STATS* pg_get_nd_stats ( const Oid  table_oid,
AttrNumber  att_num,
int  mode,
bool  only_parent 
)
static

Pull the stats object from the PgSQL system catalogs.

Used by the selectivity functions and the debugging functions.

Definition at line 932 of file gserialized_estimate.c.

References pg_nd_stats_from_tuple().

Referenced by gserialized_gist_joinsel(), and pg_get_nd_stats_by_name().

933 {
934  HeapTuple stats_tuple = NULL;
935  ND_STATS *nd_stats;
936 
937  /* First pull the stats tuple for the whole tree */
938  if ( ! only_parent )
939  {
940  POSTGIS_DEBUGF(2, "searching whole tree stats for \"%s\"", get_rel_name(table_oid)? get_rel_name(table_oid) : "NULL");
941  stats_tuple = SearchSysCache3(STATRELATTINH, ObjectIdGetDatum(table_oid), Int16GetDatum(att_num), BoolGetDatum(true));
942  if ( stats_tuple )
943  POSTGIS_DEBUGF(2, "found whole tree stats for \"%s\"", get_rel_name(table_oid)? get_rel_name(table_oid) : "NULL");
944  }
945  /* Fall-back to main table stats only, if not found for whole tree or explicitly ignored */
946  if ( only_parent || ! stats_tuple )
947  {
948  POSTGIS_DEBUGF(2, "searching parent table stats for \"%s\"", get_rel_name(table_oid)? get_rel_name(table_oid) : "NULL");
949  stats_tuple = SearchSysCache3(STATRELATTINH, ObjectIdGetDatum(table_oid), Int16GetDatum(att_num), BoolGetDatum(false));
950  if ( stats_tuple )
951  POSTGIS_DEBUGF(2, "found parent table stats for \"%s\"", get_rel_name(table_oid)? get_rel_name(table_oid) : "NULL");
952  }
953  if ( ! stats_tuple )
954  {
955  POSTGIS_DEBUGF(2, "stats for \"%s\" do not exist", get_rel_name(table_oid)? get_rel_name(table_oid) : "NULL");
956  return NULL;
957  }
958 
959  nd_stats = pg_nd_stats_from_tuple(stats_tuple, mode);
960  ReleaseSysCache(stats_tuple);
961  if ( ! nd_stats )
962  {
963  POSTGIS_DEBUGF(2,
964  "histogram for attribute %d of table \"%s\" does not exist?",
965  att_num, get_rel_name(table_oid));
966  }
967 
968  return nd_stats;
969 }
static ND_STATS * pg_nd_stats_from_tuple(HeapTuple stats_tuple, int mode)
N-dimensional statistics structure.
Here is the call graph for this function:
Here is the caller graph for this function: