select b.column_namefrom information_schema.table_constraints ainner join information_schema.constraint_column_usage bon a.constraint_name = b.constraint_namewhere a.constraint_type = ‘PRIMARY KEY‘ and a.table_name = ‘products‘go

SELECT a.name   FROM   syscolumns a   inner  join sysobjects d on a.id=d.id         where  d.name=‘products‘ and exists(SELECT 1 FROM sysobjects where xtype=‘PK‘ and  parent_obj=a.id and name in (    SELECT name  FROM sysindexes   WHERE indid in(    SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid  )))

SELECT TABLE_NAME,COLUMN_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE   WHERE TABLE_NAME=‘PDA_xjData‘