On 2019/9/5 16:31, Pavel Stehule wrote:
čt 5. 9. 2019 v 10:25 odesílatel Quan Zongliang
<zongliang.q...@postgresdata.com
<mailto:zongliang.q...@postgresdata.com>> napsal:
On 2019/9/5 15:09, Pavel Stehule wrote:
>
>
> čt 5. 9. 2019 v 8:39 odesílatel Quan Zongliang
> <zongliang.q...@postgresdata.com
<mailto:zongliang.q...@postgresdata.com>
> <mailto:zongliang.q...@postgresdata.com
<mailto:zongliang.q...@postgresdata.com>>> napsal:
>
> Dear hackers,
>
> I found that such a statement would get 0 in PL/pgSQL.
>
> PREPARE smt_del(int) AS DELETE FROM t1;
> EXECUTE 'EXECUTE smt_del(100)';
> GET DIAGNOSTICS j = ROW_COUNT;
>
> In fact, this is a problem with SPI, it does not support
getting result
> of the EXECUTE command. I made a little enhancement. Support
for the
> number of rows processed when executing INSERT/UPDATE/DELETE
statements
> dynamically.
>
>
> Is there some use case for support this feature?
>
A user deletes the data in PL/pgSQL using the above method, hoping
to do
more processing according to the number of rows affected, and found
that
each time will get 0.
Sample code:
PREPARE smt_del(int) AS DELETE FROM t1 WHERE c=$1;
EXECUTE 'EXECUTE smt_del(100)';
GET DIAGNOSTICS j = ROW_COUNT;
This has not sense in plpgsql. Why you use PREPARE statement explicitly?
Yes, I told him to do it in other ways, and the problem has been solved.
Under psql, we can get this result
flying=# EXECUTE smt_del(100);
DELETE 1
So I think this may be the negligence of SPI, it should be better to
deal with it.
IF j=1 THEN
do something
ELSIF j=0 THEN
do something
Here j is always equal to 0.
Regards
> Regards
>
> Pavel
>
>
> Regards,
> Quan Zongliang
>
