DROP INDEX
Remove an index from the database. The underlying table and its data are not affected.Syntax
Description
DROP INDEX removes a previously created index. After the index is dropped, the query planner can no longer use it to optimize queries. The table data is unchanged.
Parameters
Behavior
- Only explicitly created indexes can be dropped. Indexes automatically created for PRIMARY KEY and UNIQUE constraints cannot be dropped directly — drop the table or use ALTER TABLE instead.
- Dropping an index may degrade query performance for queries that relied on it, but does not affect correctness.
Examples
Drop an Index
Drop an Index Only if It Exists
Drop an Index in an Attached Database
See Also
- CREATE INDEX for creating indexes
- EXPLAIN for verifying query plans after dropping an index