Description
resource 
odbc_specialcolumns ( resource connection_id, int type, string qualifier, string owner, string table, int scope, int nullable)
     When the type argument is SQL_BEST_ROWID,
     odbc_specialcolumns() returns the
     column or columns that uniquely identify each row in the table.
    
     When the type argument is SQL_ROWVER, 
     odbc_specialcolumns() returns the
     optimal column or set of columns that, by retrieving values from
     the column or columns, allows any row in the specified table to be
     uniquely identified. 
    
     Returns an ODBC result identifier or FALSE on
     failure.
    
     The result set has the following columns:
     
- SCOPE 
- COLUMN_NAME 
- DATA_TYPE 
- TYPE_NAME 
- PRECISION 
- LENGTH 
- SCALE 
- PSEUDO_COLUMN 
     The result set is ordered by SCOPE.