INDEX_STATISTIC

The INDEX_STATISTIC view stores index information for the current database.

Table 1 INDEX_STATISTIC fields

Name	Type	Description
namespace	name	Tablespace to which the index belongs
table	name	Table to which the index belong
non_unique	boolean	Whether it is a unique index
key_name	name	Index name
seq_in_index	smallint	Serial number of the indexed column in the index
column_name	name	Column names of index columns
collation	text	The values are A (default, ascending), D (descending), NULL (indexes do not support sorting)
cardinality	double precision	Calculated from pg_statistic.distinct and pg_class.reltuples: stadistinct > 0: stadistinct stadistinct = 0: NULL stadistinct < 0: reltuples * stadistinct * -1
sub_part	text	Index prefix.The number of indexed characters if the column is only partially indexed, or NULL if the entire column is indexed. prefix indexing is not currently supported, NULL
packed	text	How to pack key values, specify pack_keys when creating table; otherwise return NULL. currently not supported, NULL
null	text	YES if it may contain a NULL value, otherwise
index_type	name	Indexing methods used: BTREE, HASH, etc.
comment	text	A true indisusable record in the pg_index table displays disabled, while a false record displays ''
index_comment	text	Comment information specified by COMMENT when creating an index