DROP INDEX

remove an index

English manual coverage begins with PostgreSQL 6.4. Source history and runtime observations have their own recorded version boundaries.

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anchor: SQL-DROPINDEX
file: sql-dropindex.html
lang: en
name: DROP INDEX
purpose: remove an index
purpose zh: 移除一个索引
sections same as: Unknown
slug: 18
synopsis html: DROP INDEX [ CONCURRENTLY ] [ IF EXISTS ] <em class="replaceable"><code>name</code></em> [, ...] [ CASCADE | RESTRICT ]
synopsis text: DROP INDEX [ CONCURRENTLY ] [ IF EXISTS ] name [, ...] [ CASCADE | RESTRICT ]

Syntax

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

Syntax diagrams

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Definition PG 18

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 5.15).

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.

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Source references

Full definition and evidence JSON

Definition sources

center · PostgreSQL 18 · wiki-repair-20261023:984c6f7656c3fdb1c0321439161601cf0e5838fb886bc904e49dfd49dc818ef1

Text language: en · wiki-repair-20261023:984c6f7656c3fdb1c0321439161601cf0e5838fb886bc904e49dfd49dc818ef1