Returns the indexed column name. Returns NULL for XML indexes.
INDEX_COL ( '[ database_name . [ schema_name ] .| schema_name ] table_or_view_name', index_id , key_id )
Is the name of the database.
Is the name of the schema to which the index belongs.
Is the name of the table or indexed view. table_or_view_name must be delimited by single quotation marks and can be fully qualified by database name and schema name.
Is the ID of the index. index_ID is int.
Is the index key column position. key_ID is int.
Returns NULL on error or if a caller does not have permission to view the object.
A user can only view the metadata of securables that the user owns or on which the user has been granted permission. This means that metadata-emitting, built-in functions such as INDEX_COL may return NULL if the user does not have any permission on the object. For more information, see Metadata Visibility Configuration.
A. Using INDEX_COL to return an index column name
The following example returns the column names of the two key columns in the index PK_SalesOrderDetail_SalesOrderID_LineNumber.
USE AdventureWorks2012; GO SELECT INDEX_COL (N'AdventureWorks2012.Sales.SalesOrderDetail', 1,1) AS [Index Column 1], INDEX_COL (N'AdventureWorks2012.Sales.SalesOrderDetail', 1,2) AS [Index Column 2] ; GO
Here is the result set:
Index Column 1 Index Column 2 ----------------------------------------------- SalesOrderID SalesOrderDetailID