Skip to content
PERCONA MONITORING AND MANAGEMENT DOCUMENTATION

For help, click the link below to get free database assistance or contact our experts for personalized support.

Get help from Percona

Index size is larger than data size

Description

InnoDB uses clustered PRIMARY KEY indexes, which adds the primary key to the end of all secondary indexes.

This action can make the overall index size, when it contains a large primary key, larger than the actual data. Redundant indexes can also make an index larger than the raw data.

Generally, when an index data is larger than actual data, review tables since this may be caused by one of the following:

  • Poor indexing

  • Redundant indexes

  • Large (or composite) PK

Resolution

Review tables for redundant indexes or large primary keys.

In some cases, this size is unavoidable, but small indexes and not over-indexing tables is important in data design.

Need more support from Percona?

Percona experts bring years of experience in tackling tough database performance issues and design challenges.