On 27/05/2009 1:09 AM, Leo Freitag wrote: > Hallo, > > I got some problems with a select on a foreign key with value null. > I want to filter all male singers. > > CREATE TABLE 'tblsinger' ('id' INTEGER PRIMARY KEY, 'name' TEXT, > 'fkvoice' INTEGER, 'sex' TEXT); > INSERT INTO "tblsinger" VALUES(1,'Anna Netrebko',1, 'f'); > INSERT INTO "tblsinger" VALUES(2,'Hanna Schwarz',2, 'f'); > INSERT INTO "tblsinger" VALUES(3,'Luciano Pavarotti', 3, 'm'); > INSERT INTO "tblsinger" VALUES(4,'Robert Lloyd', 4, 'm'); > INSERT INTO "tblsinger" VALUES(5,'Robby Williams', null, 'm'); > > CREATE TABLE 'tblvoice' ('id' INTEGER PRIMARY KEY, 'voice' TEXT); > INSERT INTO "tblvoice" VALUES(1,'sopran'); > INSERT INTO "tblvoice" VALUES(2,'alt'); > INSERT INTO "tblvoice" VALUES(3,'tenor'); > INSERT INTO "tblvoice" VALUES(4,'bass'); > > SELECT tblsinger.name, tblsinger.sex, tblvoice.voice FROM tblsinger, > tblvoice > WHERE tblsinger.sex = 'm' AND tblsinger.fkvoice = tblvoice.id; > > -- Result > > Luciano Pavarotti | m | tenor > Robert Lloyd | m | bass > > -- How do I have to modify the select statement to get the result below: > > Luciano Pavarotti | m | tenor > Robert Lloyd | m | bass > Robby Williams | m |
sqlite> select s.name, s.sex, v.voice from tblsinger s left outer join tblvoice v on s.fkvoice = v.id where s.sex = 'm'; Luciano Pavarotti|m|tenor Robert Lloyd|m|bass Robby Williams|m| With "visible NULL": sqlite> select s.name, s.sex, ifnull(v.voice, 'UNKNOWN') from tblsinger s left outer join tblvoice v on s.fkvoice = v.id where s.sex = 'm'; Luciano Pavarotti|m|tenor Robert Lloyd|m|bass Robby Williams|m|UNKNOWN _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users