2157 Oid table_oid1 = PG_GETARG_OID(0);
2158 text *att_text1 = PG_GETARG_TEXT_P(1);
2159 Oid table_oid2 = PG_GETARG_OID(2);
2160 text *att_text2 = PG_GETARG_TEXT_P(3);
2162 float8 selectivity = 0;
2171 elog(ERROR,
"stats for \"%s.%s\" do not exist", get_rel_name(table_oid1), text_to_cstring(att_text1));
2174 elog(ERROR,
"stats for \"%s.%s\" do not exist", get_rel_name(table_oid2), text_to_cstring(att_text2));
2177 if ( ! PG_ARGISNULL(4) )
2179 text *modetxt = PG_GETARG_TEXT_P(4);
2180 char *modestr = text_to_cstring(modetxt);
2181 if ( modestr[0] ==
'N' )
2190 PG_RETURN_FLOAT8(selectivity);
static ND_STATS * pg_get_nd_stats_by_name(const Oid table_oid, const text *att_text, int mode, bool only_parent)
Pull the stats object from the PgSQL system catalogs.
static float8 estimate_join_selectivity(const ND_STATS *s1, const ND_STATS *s2)
Given two statistics histograms, what is the selectivity of a join driven by the && or &&& operator?
N-dimensional statistics structure.