The INNODB_SYS_FIELDS table provides
      metadata about the key columns (fields) of
      InnoDB indexes, equivalent to the information
      from the SYS_FIELDS table in the
      InnoDB data dictionary.
    
For related usage information and examples, see InnoDB INFORMATION_SCHEMA System Tables.
      The INNODB_SYS_FIELDS table has these
      columns:
- INDEX_ID- An identifier for the index associated with this key field; the same value as - INNODB_SYS_INDEXES.INDEX_ID.
- NAME- The name of the original column from the table; the same value as - INNODB_SYS_COLUMNS.NAME.
- POS- The ordinal position of the key field within the index, starting from 0 and incrementing sequentially. When a column is dropped, the remaining columns are reordered so that the sequence has no gaps. 
Example
mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FIELDS WHERE INDEX_ID = 117\G
*************************** 1. row ***************************
INDEX_ID: 117
    NAME: col1
     POS: 0Notes
- You must have the - PROCESSprivilege to query this table.
- Use the - INFORMATION_SCHEMA- COLUMNStable or the- SHOW COLUMNSstatement to view additional information about the columns of this table, including data types and default values.