On Mon, Sep 21, 2015 at 6:49 PM, Richard Hipp <drh at sqlite.org> wrote:
> On 9/21/15, Hugues Bruant <hugues at aerofs.com> wrote: > > Table schema: > > > > CREATE TABLE cv (cv_s integer not null, cv_o blob not null, cv_t integer > > not null, primary key(cv_s, cv_o)); > > > > Prepared statement: > > > > UPDATE cv SET cv_t=? where cv_s=? and cv_o=?; > > My guess is that the WHERE clause matches no rows. So it isn't > silently failing, it is doing exactly what it is suppose to do: > Update only those rows you have specified. > I wish it where that simple. The where clause should match, as evidenced by the fact that: SELECT cv_t from cv where cv_s=? and cv_o=?; returns the correct value both before and after the failing UPDATE. If that's not convincing enough, I should mention that the code checks the change count and falls back to an INSERT if the UPDATE reports that no rows where updated. This results in a SQLITE_CONSTRAINT error, which is how we discovered that the update was failing in the first place.
