On Fri, Oct 1, 2021, at 3:07 PM, PG Bug reporting form wrote:
Suppose we have 2 tablespaces:
pg_default (which is slow)
fast
We also have a partitioned table:
create table a (id serial not null, b int not null primary key, c int not
null, d int) partition by hash (b);
and 2 partitions:
create table a_1 partition of a for values with (modulus 2, remainder 0);
create table a_2 partition of a for values with (modulus 2, remainder 1)
tablespace fast;
This successfully allocates table a_2 pages within the 'fast' tablespace;
but this fails to allocate a_2_pkey primary key index there too and the
result is the index is allocated on tablespace oid(0) which means pg_default
I guess, at least the corresponding relfilenode is allocated within the
pg_default tablespace.
That's how it was designed. TABLESPACE clause at the end of CREATE TABLE set
the tablespace only for the table. The index is stored based on the
default_tablespace [1] value.
Since there is no way to specify USING INDEX TABLESPACE for partitions, you
should set default_tablespace to achieve what you want.
CREATE TABLE a (
id serial NOT NULL,
b int NOT NULL PRIMARY KEY,
c int NOT NULL,
d int
) PARTITION BY hash (b);
CREATE TABLE a_1 PARTITION OF a
FOR VALUES WITH (MODULUS 3, REMAINDER 0);
SET default_tablespace TO 'fast';
-- the TABLESPACE clause is not required
-- table -> fast ; index -> fast
CREATE TABLE a_2 PARTITION OF a
FOR VALUES WITH (MODULUS 3, REMAINDER 1) TABLESPACE fast;
-- table -> tablespace slow ; index -> tablespace fast
CREATE TABLE a_3 PARTITION OF a
FOR VALUES WITH (MODULUS 3, REMAINDER 2) TABLESPACE slow;
RESET default_tablespace;