pg_index
#
The catalog pg_index
contains part of the information
about indexes. The rest is mostly in
pg_class
.
Table 55.27. pg_index
Columns
Column Type Description |
---|
The OID of the |
The OID of the |
The total number of columns in the index (duplicates
|
The number of key columns in the index, not counting any included columns, which are merely stored and do not participate in the index semantics |
If true, this is a unique index |
This value is only used for unique indexes. If false, this unique index will consider null values distinct (so the index can contain multiple null values in a column, the default PostgreSQL behavior). If it is true, it will consider null values to be equal (so the index can only contain one null value in a column). |
If true, this index represents the primary key of the table
( |
If true, this index supports an exclusion constraint |
If true, the uniqueness check is enforced immediately on
insertion
(irrelevant if |
If true, the table was last clustered on this index |
If true, the index is currently valid for queries. False means the
index is possibly incomplete: it must still be modified by
|
If true, queries must not use the index until the |
If true, the index is currently ready for inserts. False means the
index must be ignored by |
If false, the index is in process of being dropped, and should be ignored for all purposes (including HOT-safety decisions) |
If true this index has been chosen as “replica identity”
using |
This is an array of |
For each column in the index key
( |
For each column in the index key
( |
This is an array of |
Expression trees (in |
Expression tree (in |