Обсуждение: Don't want blank data
Greetings, Is there a way to have postgresql always return a value for each row requested? To be more clear, if I were usinga Perl SQL hybrid I would write something like SELECT computer_ip or 'unset' FROM computers; So that if computers.computer_ip is NULL or '' I will get 'unset' back from the database. I hope this makes sense and somebodycan point me in a good direction -- Dave
On Thu, 25 Jan 2001, David Olbersen wrote: > Greetings, > Is there a way to have postgresql always return a value for each row > requested? To be more clear, if I were using a Perl SQL hybrid I would write > something like > > SELECT computer_ip or 'unset' FROM computers; > > So that if computers.computer_ip is NULL or '' I will get 'unset' back from > the database. I hope this makes sense and somebody can point me in a good > direction Perhaps:select case when computer_ip is null or computer_ip='' then 'unset'::text else computer_ip end from computers; (the ::text should probably be whatever type computer_ip is)...
David Olbersen wrote: >Greetings, > Is there a way to have postgresql always return a value for each row > requested? Tobe more clear, if I were using a Perl SQL hybrid I would wri >te > something like > > SELECT computer_ip or 'unset'FROM computers; > > So that if computers.computer_ip is NULL or '' I will get 'unset' back fro >m > the database.I hope this makes sense and somebody can point me in a good > direction SELECT COALESCE(computer_ip,'unset') AS computer_ip FROM computers; COALESCE() returns the leftmost non-null value from its parameters. -- Oliver Elphick Oliver.Elphick@lfix.co.uk Isle of Wight http://www.lfix.co.uk/oliver PGP: 1024R/32B8FAA1: 97 EA 1D 47 72 3F 28 47 6B 7E 39 CC 56 E4 C1 47 GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839 932A 614D 4C34 3E1D 0C1C ======================================== "My little children, let us not love in word, neither in tongue; but in deedand in truth." I John 3:18