MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6
      The INNODB_SYS_FOREIGN_COLS table
      provides status information about the columns of
      InnoDB foreign keys, equivalent to the
      information from the SYS_FOREIGN_COLS 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_COLS table has
      these columns:
    
          ID
        
          The foreign key index associated with this index key field,
          using the same value as
          INNODB_SYS_FOREIGN.ID.
        
          FOR_COL_NAME
        
The name of the associated column in the child table.
          REF_COL_NAME
        
The name of the associated column in the parent table.
          POS
        
The ordinal position of this key field within the foreign key index, starting from 0.
mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS WHERE ID = 'test/fk1'\G
*************************** 1. row ***************************
          ID: test/fk1
FOR_COL_NAME: parent_id
REF_COL_NAME: id
         POS: 0
          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.