{ “title”: “Bitmap Index”, “language”: “en” }

Bitmap Index

Users can speed up queries by creating a bitmap index This document focuses on how to create an index job, as well as some considerations and frequently asked questions when creating an index.

Glossary

  • bitmap index: a fast data structure that speeds up queries

Basic Principles

Creating and dropping index is essentially a schema change job. For details, please refer to Schema Change.

Syntax

There are two forms of index creation and modification related syntax, one is integrated with alter table statement, and the other is using separate create/drop index syntax

  1. Create Index

    Please refer to CREATE INDEX or ALTER TABLE, You can also specify a bitmap index when creating a table, Please refer to CREATE TABLE

  2. Show Index

    Please refer to SHOW INDEX

  3. Drop Index

    Please refer to DROP INDEX or ALTER TABLE

Create Job

Please refer to Schema Change

View Job

Please refer to Schema Change

Cancel Job

Please refer to Schema Change

Notice

  • Currently only index of bitmap type is supported.
  • The bitmap index is only created on a single column.
  • Bitmap indexes can be applied to all columns of the Duplicate data model and key columns of the Aggregate and Uniq models.
  • The data types supported by bitmap indexes are as follows:
    • TINYINT
    • SMALLINT
    • INT
    • UNSIGNEDINT
    • BIGINT
    • CHAR
    • VARCHAR
    • DATE
    • DATETIME
    • LARGEINT
    • DECIMAL
    • BOOL
  • The bitmap index takes effect only in segmentV2. The table's storage format will be converted to V2 automatically when creating index.