Documentation Home
MySQL 5.7 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 36.3Mb
PDF (A4) - 36.4Mb
PDF (RPM) - 35.8Mb
HTML Download (TGZ) - 9.5Mb
HTML Download (Zip) - 9.5Mb
HTML Download (RPM) - 8.3Mb
Man Pages (TGZ) - 235.2Kb
Man Pages (Zip) - 346.9Kb
Info (Gzip) - 3.3Mb
Info (Zip) - 3.3Mb
Excerpts from this Manual

MySQL 5.7 Reference Manual  /  ...  /  The INFORMATION_SCHEMA INNODB_SYS_FOREIGN Table


The INNODB_SYS_FOREIGN table provides metadata about InnoDB foreign keys, equivalent to the information from the SYS_FOREIGN table in the InnoDB data dictionary.

For related usage information and examples, see Section 14.16.3, “InnoDB INFORMATION_SCHEMA System Tables”.

The INNODB_SYS_FOREIGN table has these columns:

  • ID

    The name (not a numeric value) of the foreign key index, preceded by the schema (database) name (for example, test/products_fk).


    The name of the child table in this foreign key relationship.


    The name of the parent table in this foreign key relationship.

  • N_COLS

    The number of columns in the foreign key index.

  • TYPE

    A collection of bit flags with information about the foreign key column, ORed together. 0 = ON DELETE/UPDATE RESTRICT, 1 = ON DELETE CASCADE, 2 = ON DELETE SET NULL, 4 = ON UPDATE CASCADE, 8 = ON UPDATE SET NULL, 16 = ON DELETE NO ACTION, 32 = ON UPDATE NO ACTION.


*************************** 1. row ***************************
      ID: test/fk1
FOR_NAME: test/child
REF_NAME: test/parent
  N_COLS: 1
    TYPE: 1


  • You must have the PROCESS privilege to query this table.

  • Use the INFORMATION_SCHEMA COLUMNS table or the SHOW COLUMNS statement to view additional information about the columns of this table, including data types and default values.