SQL DROP INDEX Keyword

The DROP INDEX command is used to remove an index from a table. Indexes speed up queries, but removing unnecessary indexes can sometimes improve performance for update operations.

Dropping an Index

The syntax for dropping an index varies slightly depending on the database system you're using. Here's how to do it in a few popular systems.

MS Access

In MS Access, you specify the index name and the table name.

DROP INDEX index_name
ON table_name;
      

SQL Server

In SQL Server, the table name is part of the index name specification (using dot notation).

DROP INDEX table_name.index_name;
      

DB2/Oracle

In DB2 and Oracle, only the index name is needed to drop the index.

DROP INDEX index_name;
      

MySQL

In MySQL, you use the ALTER TABLE command to drop an index.

ALTER TABLE table_name
DROP INDEX index_name;