MySQL 8.0.13 and higher supports functional key parts (see Functional Key Parts), which affects both the COLUMN_NAME  and EXPRESSION  columns: 

•For a nonfunctional key part, COLUMN_NAME  indicates the column indexed by the key part and EXPRESSION  is NULL . 

•For a functional key part, COLUMN_NAME  column is NULL  and EXPRESSION  indicates the expression for the key part. 

## Notes 

•There is no standard INFORMATION_SCHEMA  table for indexes. The MySQL column list is similar to what SQL Server 2000 returns for sp_statistics , except that QUALIFIER  and OWNER  are replaced with CATALOG  and SCHEMA , respectively. 

Information about table indexes is also available from the SHOW INDEX  statement. See Section 13.7.7.22, “SHOW INDEX Statement” . The following statements are equivalent: 

SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE table_name = ’ tbl_name ’ AND table_schema = ’ db_name ’ SHOW INDEX FROM tbl_name FROM db_name 

## 26.3.35 The INFORMATION_SCHEMA ST_GEOMETRY_COLUMNS Table 

The ST_GEOMETRY_COLUMNS  table provides information about table columns that store spatial data. This table is based on the SQL/MM (ISO/IEC 13249-3) standard, with extensions as noted. MySQL implements ST_GEOMETRY_COLUMNS  as a view on the INFORMATION_SCHEMA COLUMNS  table. 

The ST_GEOMETRY_COLUMNS  table has these columns: 

• TABLE_CATALOG 

The name of the catalog to which the table containing the column belongs. This value is always def . 

• TABLE_SCHEMA 

The name of the schema (database) to which the table containing the column belongs. 

• TABLE_NAME 

The name of the table containing the column. 

• COLUMN_NAME 

The name of the column. 

• SRS_NAME 

The spatial reference system (SRS) name. 

• SRS_ID 

The spatial reference system ID (SRID). 

• GEOMETRY_TYPE_NAME 

