Re: new "row-level lock" error messages

On Tue, Jul 23, 2013 at 2:16 PM, Alvaro Herrera
<alvherre(at)2ndquadrant(dot)com> wrote:
> Alvaro Herrera wrote:
>> Peter Eisentraut wrote:
>>
>> > I would suggest that these changes be undone, except that the old
>> > "SELECT FOR ..." be replaced by a dynamic string that reverse-parses the
>> > LockingClause to provide the actual clause that was used.
>>
>> Here's a patch for this.
>
> Pushed to 9.3 and master. Sample output:
>
> alvherre=# select * from foo, bar for update of foof for share of bar;
> ERROR: relation "foof" in FOR UPDATE clause not found in FROM clause
>
> alvherre=# select * from foo, bar for update of foo for share of barf;
> ERROR: relation "barf" in FOR SHARE clause not found in FROM clause
>
> Amusingly, the only test in which these error messages appeared, in
> contrib/file_fdw, was removed after the two commits that changed the
> wording. So there's not a single test which needed to be tweaked for
> this change.

The fact that there are no tests of this functionality is probably not
a good thing. We should add some. At the moment, the following test
case crashes, and it looks like this commit is responsible:

create table test_update2 (id integer);
DECLARE test_update_cursor CURSOR FOR SELECT id, MIN(id) FROM
test_update2 GROUP By id HAVING MIN(id) < 1 FOR UPDATE;

--
Robert Haas
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