On Thu, Aug 14, 2003 at 01:43:37AM -0400, Christopher Browne was heard to remark: > Linas wrote: > > On Wed, Aug 13, 2003 at 09:39:05PM -0500, Matthew Vanecek was heard to remark > > > Well, specifically the book table upgrade was failing due to (I believe) > > > Postgres becoming a little more ANSI-SQL compliant (that's not a theme > > > or anything for me, is it!?). NOT NULL constraints are not allowed on > > > the ADD COLUMN statement in SQL, and thus not in Postgresql (anymore). > > > > OK. But I cannot begin to imagine why anyone would remove a harmless > > feature that doesn't actually break compliance. > > According to the documentation: > > "A new column cannot have a not-null constraint since the column initially has > to contain null values." > > Which seems to make sense. > > At the time you add the column, it's empty, isn't it? > > That breaks the constraint at the instant that it was applied, which means > that the constraint system has to be broken.
Well, there's two ways to interpret the meaning. You suggest 'constraint: never let the data in the column be null' The alternative is 'never allow an INSERT/UPDATE that would leave the column null.' Being a proceedural rather than a constraint kind-of guy, I went with the latter. It seems like one is throwing out the baby with the bathwater but hey I've sat on standards committes before so I know ... --linas -- pub 1024D/01045933 2001-02-01 Linas Vepstas (Labas!) <[EMAIL PROTECTED]> PGP Key fingerprint = 8305 2521 6000 0B5E 8984 3F54 64A9 9A82 0104 5933 _______________________________________________ gnucash-devel mailing list [EMAIL PROTECTED] http://www.gnucash.org/cgi-bin/mailman/listinfo/gnucash-devel
