> 2)if two ore more record have the same value of the maxim value of the "ora" > to select oly one of them
At this point you really have to decide which criteria you use for this deciding. I strongly suggest to use a uniqe ID for each row in the table(in your case it is important): CREATE TABLE "temp50" ( id serial primary key, "gc" character varying(36), "co" character varying(7), "data" date, "ora" smallint ); Your selection can be made in many ways, but you have to decide the second criteria. One more thing: Your table datas are: 1 >> 5003707G9G9419 22012BB 10-14-2004 82 2 >> 5003707G9G9419 22012BC 10-14-2004 44 3 >> 5003707G9G9419 22022BB 10-14-2004 82 4 >> 5003707G9G9420 22022BC 10-18-2004 49 The rows no 1 and 3 are "redundant" data's(they are the same). Do you really want this??? Best regards, Andy. ----- Original Message ----- From: "cristivoinicaru" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, October 25, 2004 11:13 AM Subject: [SQL] sql > I have a postgres table like this: > > CREATE TABLE "temp50" ( > "gc" character varying(36), > "co" character varying(7), > "data" date, > "ora" smallint > > ); > > It contains the following records: > > 5003707G9G9419 22012BB 10-14-2004 82 > 5003707G9G9419 22012BC 10-14-2004 44 > 5003707G9G9419 22022BB 10-14-2004 82 > 5003707G9G9420 22022BC 10-18-2004 49 > > I'd like the result of the sql interogation to be like this: > > 5003707G9G9419 22012BB 10-14-2004 82 > 5003707G9G9420 22022BC 10-18-2004 49 > > > Explanations: > I want like sql interogation to select only one record from each "gc" group > record (who has the same code "gc" (that means that the "gc" field will be > unique key)) with the following two condition: > 1)from each "gc" group of records to select the record who has the value of > "ora" field maxim. > 2)if two ore more record have the same value of the maxim value of the "ora" > to select oly one of them > > Thanks! > > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend > ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
