am 17.06.2005, um 13:01:15 +0300 mailte Fatih Cerit folgendes: > Dear ALL > > I have a problem with function substr or char_length or both. I guery A2 > and it works fine. But sometimes gives 'ERROR: negative substring length > not allowed'. When I test many many times with diffrent values, never gives > error. Sample table and query below. > > > > A1 A2 > ------------------- > 1 1957 > 2 197 > 3 19 > 4 > 5 NULL > 6 1 > 7 195 > > > Select * from tbl_xxx where > tbl_xxx.A2=substr('196895588454554545454',0,char_length(tbl_xxx.A2)+1);
Perhaps because char_length() returns NULL and this is a invalid value for substr(). Use coalesce(): ... substr('196895588454554545454',0,coalesce(char_length(tbl_xxx.A2),0)+1); Regards, Andreas -- Andreas Kretschmer (Kontakt: siehe Header) Heynitz: 035242/47212, D1: 0160/7141639 GnuPG-ID 0x3FFF606C http://wwwkeys.de.pgp.net === Schollglas Unternehmensgruppe === ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])