INDEX_STAITISTIC

INDEX_STAITISTIC displays information about indexes in the current database.

Table 1 INDEX_STAITISTIC columns

Name	Type	Description
namespace	name	Specifies a tablespace to which an index belongs.
table	name	Specifies a table to which the index belongs.
non_unique	boolean	Indicates whether the index is unique.
key_name	name	Specifies an index name.
seq_in_index	smallint	Specifies sequence number of the index column in the index.
column_name	name	Specifies an index column name.
collation	text	The value can be A (default value, indicating an ascending order), D (descending order), or NULL (the index does not support sorting).
cardinality	double precision	By calculating pg_statistic.stadistinct and pg_class.reltuples, you can obtain: stadistinct > 0: stadistinct stadistinct = 0: NULL stadistinct < 0: reltuples * stadistinct * -1 .
sub_part	text	Index prefix. If the column is only partially indexed, the value is the number of index characters. If the entire column is indexed, the value is NULL. Currently, the prefix index is not supported. The value is NULL.
packed	text	Specifies how to pack key values. pack_keys is specified when a table is created. Otherwise, null is returned. Not supported currently. The value is NULL.
null	text	Yes if the value is null.
index_type	name	Specifies the index method, such as Btree, and Hash.
comment	text	If indisusable is set to true in the pg_index table, disabled is displayed. If it is set to false, '' is displayed.
index_comment	text	Specifies comments when an index is created.