On Wed, Apr 4, 2012 at 8:00 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > umi.tan...@gmail.com writes: >> http://www.postgresql.org/docs/9.1/static/spi-spi-execute.html > >> === >> SPI_execute("INSERT INTO foo SELECT * FROM bar", false, 5); >> will allow at most 5 rows to be inserted into the table. >> === > >> This seems not true unless I'm missing something. > > Hmm ... that did work as described, until we broke it :-(. This is an > oversight in the 9.0 changes that added separate ModifyTuple nodes to > plan trees. ModifyTuple doesn't return after each updated row, unless > there's a RETURNING clause; which means that the current_tuple_count > check logic in ExecutePlan() no longer stops execution as intended. > > Given the lack of complaints since 9.0, maybe we should not fix this > but just redefine the new behavior as being correct? But it seems > mighty inconsistent that the tuple limit would apply if you have > RETURNING but not when you don't. In any case, the ramifications > are wider than one example in the SPI docs. > > Thoughts?
To be honest, I was surprised when I found tcount parameter is said to be applied to even INSERT. I believe people think that parameter is to limit memory consumption when returning tuples thus it'd be applied for only SELECT or DML with RETURNING. So I'm +1 for non-fix but redefine the behavior. Who wants to limit the number of rows processed inside the backend, from SPI? Thanks, -- Hitoshi Harada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
