> 2020年1月29日 下午9:48，Robert Haas <robertmhaas@gmail.com> 写道： > > On Tue, Jan 28, 2020 at 12:12 PM 曾文旌(义从) <wenjing.zwj@alibaba-inc.com> wrote: >>> Opinion by Pavel >>> + rel->rd_islocaltemp = true; <<<<<<< if this is valid, then the name of field "rd_islocaltemp" is not probably best >>> I renamed rd_islocaltemp >> >> I don't see any change? >> >> Rename rd_islocaltemp to rd_istemp in global_temporary_table_v8-pg13.patch > > In view of commit 6919b7e3294702adc39effd16634b2715d04f012, I think > that this has approximately a 0% chance of being acceptable. If you're > setting a field in a way that is inconsistent with the current use of > the field, you're probably doing it wrong, because the field has an > existing purpose to which new code must conform. And if you're not > doing that, then you don't need to rename it. Thank you for pointing it out. I've rolled back the rename. But I still need rd_localtemp to be true, The reason is that 1 GTT The GTT needs to support DML in read-only transactions ,like local temp table. 2 GTT does not need to hold the lock before modifying the index buffer ,also like local temp table.
Please give me feedback.
maybe some like
rel->rd_globaltemp = true;
and somewhere else
if (rel->rd_localtemp || rel->rd_globaltemp)
{
...
}
I tested this patch again and I am very well satisfied with behave.
what doesn't work still - TRUNCATE statement
postgres=# insert into foo select generate_series(1,10000); INSERT 0 10000 postgres=# \dt+ foo List of relations ┌────────┬──────┬───────┬───────┬─────────────┬────────┬─────────────┐ │ Schema │ Name │ Type │ Owner │ Persistence │ Size │ Description │ ╞════════╪══════╪═══════╪═══════╪═════════════╪════════╪═════════════╡ │ public │ foo │ table │ pavel │ session │ 384 kB │ │ └────────┴──────┴───────┴───────┴─────────────┴────────┴─────────────┘ (1 row)
postgres=# truncate foo; TRUNCATE TABLE postgres=# \dt+ foo List of relations ┌────────┬──────┬───────┬───────┬─────────────┬───────┬─────────────┐ │ Schema │ Name │ Type │ Owner │ Persistence │ Size │ Description │ ╞════════╪══════╪═══════╪═══════╪═════════════╪═══════╪═════════════╡ │ public │ foo │ table │ pavel │ session │ 16 kB │ │ └────────┴──────┴───────┴───────┴─────────────┴───────┴─────────────┘ (1 row)
