On Jul 30, 3:27 am, al...@xxxxxxxxxxxxxxxxx (Alban Hertroys) wrote: > Nis Jørgensen wrote: > > Alban Hertroys skrev: > > >> Presumably he wanted col2 like E'%\\\\N%'. > >> But doesn't \N mean NULL, or would the OP be looking for literal '\N' > >> strings in his data? Because if he's looking for NULLs it may be better > >> to query for col2 IS NULL. > > > My guess is that this string was used to signify NULL in the file > > originally imported into the db. > > Which is basically what I was pointing out ;) > It's all speculation anyway, we're guessing at what problem the OP tries > to solve. > > I think either he is looking for NULL column values that exist in his > input file as '\N' strings (strings cannot contain NULLs, so using > "like" is pointless), or he is looking for failed conversions of \N from > his input file that thus may have ended up as literal \N characters in > column data. > > In the latter case there shouldn't be any columns that match "like > '%\\\\N%'" but not "= '\\\\N'". OTOH, we may be talking about an import > failure, in which case anything is possible. Fixing that would probably > be more difficult than fixing the cause of the failure and re-doing the > import. > > As I said, it's all speculation. Without input from the OP there's not > much point in continuing this discussion. > > Regards, > -- > Alban Hertroys > al...@xxxxxxxxxxxxxxxxx > > magproductions b.v. > > T: ++31(0)534346874 > F: ++31(0)534346876 > M: > I:www.magproductions.nl > A: Postbus 416 > 7500 AK Enschede > > // Integrate Your World // > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Have you searched our list archives? > > http://archives.postgresql.org/ oh yes! You all are exactly right.I exported a table and all nulls became \N and when i imported it \n remained \N and did not convert to NULL.So I updates all \N s with '' now. Thank you all for your input.I got to learn a lot from you. pc PS: Please refer to me as she :) ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
