ALTER-TABLE-BITMAP

ALTER-TABLE-BITMAP

Name

ALTER TABLE BITMAP

Description

This statement is used to perform a bitmap index operation on an existing table.

grammar:

ALTER TABLE [database.]table alter_clause;

The alter_clause of bitmap index supports the following modification methods

1. Create a bitmap index

   Syntax:

ADD INDEX [IF NOT EXISTS] index_name (column [, ...],) [USING BITMAP] [COMMENT 'balabala'];

Notice:

• Currently only supports bitmap indexes
• BITMAP indexes are only created on a single column

2. Delete the index

Syntax:

DROP INDEX [IF EXISTS] index_name;

Example

1. Create a bitmap index for siteid on table1

ALTER TABLE table1 ADD INDEX [IF NOT EXISTS] index_name (siteid) [USING BITMAP] COMMENT 'balabala';

2. Delete the bitmap index of the siteid column on table1

ALTER TABLE table1 DROP INDEX [IF EXISTS] index_name;

Keywords

ALTER, TABLE, BITMAP, INDEX, ALTER TABLE

Best Practice