On Sat, Oct 5, 2013 at 7:38 AM, Amit Kapila <amit.kapil...@gmail.com> wrote: > On Sun, Sep 29, 2013 at 1:39 PM, Ian Lawrence Barwick <barw...@gmail.com> > wrote: >> Hi, >> >> This patch implements the following TODO item: >> >> Allow COPY in CSV mode to control whether a quoted zero-length >> string is treated as NULL >> >> Currently this is always treated as a zero-length string, >> which generates an error when loading into an integer column >> >> Re: [PATCHES] allow CSV quote in NULL >> http://archives.postgresql.org/pgsql-hackers/2007-07/msg00905.php >> >> >> http://wiki.postgresql.org/wiki/Todo#COPY >> >> >> I had a very definite use-case for this functionality recently while >> importing >> CSV files generated by Oracle, and was somewhat frustrated by the existence >> of a FORCE_NOT_NULL option for specific columns, but not one for >> FORCE_NULL. > > While going through documentation of this patch to understand it's > usage, I found a small mistake. > > + Force the specified columns' values to be converted to > <literal>NULL</> > + if the value contains an empty string. > > It seems quote after columns is wrong.
That's a correct plural possessive in English, but in might be better worded as "Force any empty string encountered in the input for the specified columns to be interpreted as a NULL value." > Also if your use case is to treat empty strings as NULL (as per above > documentation), can't it be handled with "WITH NULL AS" option. > For example, something like: > > postgres=# COPY testnull FROM stdin with CSV NULL AS E''; > Enter data to be copied followed by a newline. > End with a backslash and a period on a line by itself. >>> 50, >>> \. > postgres=# select * from testnull; > a | b > ----+------ > 50 | NULL > (1 row) Good point. If this patch is just implementing something that can already be done with another syntax, we don't need it. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
