This query will give you the table name and column name on which you have defined the primary key. You can use this to get columns on which the primary key is based. I find it very useful when i need to define the FK relationship for other tables in PowerDesigner. Try to do the same thing using system tables, i will really appreciate that, because i didn't find it that easy.
MCP, MCAD (.Net), MCSD, MCDBA