NAME

       DROP_INDEX - remove an index

SYNOPSIS

       DROP INDEX [ CONCURRENTLY ] [ IF EXISTS ] name [, ...] [ CASCADE | RESTRICT ]

DESCRIPTION

       DROP INDEX drops an existing index from the database system. To execute this command you
       must be the owner of the index.

PARAMETERS

       CONCURRENTLY
           Drop the index without locking out concurrent selects, inserts, updates, and deletes
           on the index's table. A normal DROP INDEX acquires an ACCESS EXCLUSIVE lock on the
           table, blocking other accesses until the index drop can be completed. With this
           option, the command instead waits until conflicting transactions have completed.

           There are several caveats to be aware of when using this option. Only one index name
           can be specified, and the CASCADE option is not supported. (Thus, an index that
           supports a UNIQUE or PRIMARY KEY constraint cannot be dropped this way.) Also, regular
           DROP INDEX commands can be performed within a transaction block, but DROP INDEX
           CONCURRENTLY cannot. Lastly, indexes on partitioned tables cannot be dropped using
           this option.

           For temporary tables, DROP INDEX is always non-concurrent, as no other session can
           access them, and non-concurrent index drop is cheaper.

       IF EXISTS
           Do not throw an error if the index does not exist. A notice is issued in this case.

       name
           The name (optionally schema-qualified) of an index to remove.

       CASCADE
           Automatically drop objects that depend on the index, and in turn all objects that
           depend on those objects (see Section 5.14).

       RESTRICT
           Refuse to drop the index if any objects depend on it. This is the default.

EXAMPLES

       This command will remove the index title_idx:

           DROP INDEX title_idx;

COMPATIBILITY

       DROP INDEX is a PostgreSQL language extension. There are no provisions for indexes in the
       SQL standard.

SEE ALSO

       CREATE INDEX (CREATE_INDEX(7))