get this type of information using the techniques from Section 15.17, “InnoDB Monitors” , setting up InnoDB monitors and parsing the output from the SHOW ENGINE INNODB STATUS  statement. The InnoDB INFORMATION_SCHEMA  table interface allows you to query this data using SQL. 

InnoDB INFORMATION_SCHEMA  schema object tables include the tables listed below. 

INNODB_DATAFILES INNODB_TABLESTATS INNODB_FOREIGN INNODB_COLUMNS INNODB_INDEXES INNODB_FIELDS INNODB_TABLESPACES INNODB_TABLESPACES_BRIEF INNODB_FOREIGN_COLS INNODB_TABLES 

The table names are indicative of the type of data provided: 

• INNODB_TABLES  provides metadata about InnoDB  tables. 

• INNODB_COLUMNS  provides metadata about InnoDB  table columns. 

• INNODB_INDEXES  provides metadata about InnoDB  indexes. 

• INNODB_FIELDS  provides metadata about the key columns (fields) of InnoDB  indexes. 

• INNODB_TABLESTATS  provides a view of low-level status information about InnoDB  tables that is derived from in-memory data structures. 

• INNODB_DATAFILES  provides data file path information for InnoDB  file-per-table and general tablespaces. 

• INNODB_TABLESPACES  provides metadata about InnoDB  file-per-table, general, and undo tablespaces. 

• INNODB_TABLESPACES_BRIEF  provides a subset of metadata about InnoDB  tablespaces. 

• INNODB_FOREIGN  provides metadata about foreign keys defined on InnoDB  tables. 

• INNODB_FOREIGN_COLS  provides metadata about the columns of foreign keys that are defined on InnoDB  tables. 

InnoDB INFORMATION_SCHEMA  schema object tables can be joined together through fields such as TABLE_ID , INDEX_ID , and SPACE , allowing you to easily retrieve all available data for an object you want to study or monitor. 

Refer to the InnoDB  INFORMATION_SCHEMA documentation for information about the columns of each table. 

## Example 15.2 InnoDB INFORMATION_SCHEMA Schema Object Tables 

This example uses a simple table ( t1 ) with a single index ( i1 ) to demonstrate the type of metadata found in the InnoDB INFORMATION_SCHEMA  schema object tables. 

1. Create a test database and table t1 : 

mysql> CREATE DATABASE test; mysql> USE test; mysql> CREATE TABLE t1 ( 

