No, that doesn't sound right. I'm not trying to insert a literal '\s' or anything (whatever the heck that might mean). The sequence '\s' is to be interpreted by the ~ regular expression operator, isn't it? I would imagine that I would want the sequence of BACKSLASH + LETTER_S to go through to the ~ operator untouched. I don't _want_ it to do any escaping, so the E prefix feels wrong, no? I'm still confused, -Patrick On Wed, Dec 23, 2009 at 3:32 PM, Bill Moran <wmoran@xxxxxxxxxxxxxxxxx> wrote: > In response to "Patrick M. Rutkowski" <rutski89@xxxxxxxxx>: > >> I just ran something like: >> ============================================= >> UPDATE my_table SET colname = NULL WHERE colname ~ '^\s*$' >> ============================================= >> >> >> I got the following warnings/hints as a result: >> ============================================= >> WARNING: nonstandard use of escape in a string literal >> HINT: USE the escape string syntax for escapes, e.g., E'\r\n'. >> UPDATE 500 >> ============================================= >> >> >> Oddly it actually updated, and did just exactly what I wanted! :-) >> >> So what am I to make of those weird hints and warning? > > The SQL spec says that inside '', strings are to be interpreted exactly, > except for the string '', which is converted to '. > > Obviously, 99% of the world thinks they should be able to use \ to > escape special characters (like \n and \t). PostgreSQL has historically > supported the more common use and not been strict to the standard. > > This is changing. Newer versions of PG will (someday) no longer support > that syntax, and the warnings are alerting you to code that will stop > working when that happens. > > In any event, you can work around this using the string escape syntax > (i.e. WHERE colname ~ E'^\s*$') and the official documentation is here: > http://www.postgresql.org/docs/8.4/static/sql-syntax-lexical.html#SQL-SYNTAX-STRINGS > > -- > Bill Moran > http://www.potentialtech.com > http://people.collaborativefusion.com/~wmoran/ > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
