Kenneth, > i translated this as: > > field varchar(2) check (field in (null,'a','b','c')),
While this isn't the question you asked, might I encourage you to use DOMAINs instead? I.e.: CREATE DOMAIN abc_col AS TEXT CHECK VALUE IN ( 'a', 'b', 'c' ); Then you declare the table as: table ( field abc_col, ); I find that DOMAINs give vastly enhanced managability compared to table constraints. -- Josh Berkus Aglio Database Solutions San Francisco ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match