On Sun, Aug 31, 2008 at 11:31:32PM -0400, Aaron Burnett wrote: > table1 has 25 columns > table2 is a subset of table1 (create table2 as select > id,field1,field2,field3,field4,field5,field6 from table1) with just 7 > columns > There is a primary key on ID > table2 was exported to a CSV, truncated, then the ³cleaned² CSV was > re-imported to table2 > In a nutshell I need to find the difference between the 6 columns in table2 > vs table1 and update table1, again, with the ID column being the pk. update table1 as t1 set field1 = t2.field1, field2 = t2.field2, field3 = t2.field3, field4 = t2.field4, field5 = t2.field5, field6 = t2.field6 from table2 t2 where t1.id = t2.id and ( ( t1.field1 is distinct from t2.field1 ) OR ( t1.field2 is distinct from t2.field2 ) OR ( t1.field3 is distinct from t2.field3 ) OR ( t1.field4 is distinct from t2.field4 ) OR ( t1.field5 is distinct from t2.field5 ) OR ( t1.field6 is distinct from t2.field6 ) ); should work. Best regards, depesz -- Linkedin: http://www.linkedin.com/in/depesz / blog: http://www.depesz.com/ jid/gtalk: depesz@xxxxxxxxxx / aim:depeszhdl / skype:depesz_hdl / gg:6749007