SQL: Multiple paranetheses not parsed correctly (error: 'only hash column group is allowed')

[stevecookform3]

Jira Link: DB-2441
Example:

> create index on mytable ((myfield));
ERROR:  only hash column group is allowed
LINE 1: create index on mytable ((myfield));
                             ^

but create index on mytable (myfield); with just a single set of paranetheses works fine.

possibly related to #3981 ?

[ddorian]

Confirming issue:

postgres=# create table test(id bigserial, b bigint);
CREATE TABLE
postgres=# create index on test((b));
ERROR:  only hash column group is allowed
LINE 1: create index on test((b));
                             ^
postgres=# create index on test(b);
CREATE INDEX

[ndeodhar]

Hi @stevecookform3 , yes, this is similar to #3981. It's intentional behavior for now. We only allow column groups for HASH columns.
So, create index on mytable((myfield) HASH) will work
but the follow variants won't work:
create index on mytable((myfield) ASC)
create index on mytable((myfield) DESC)
create index on mytable((myfield)) // Same as create index on mytable((myfield) ASC)

[tverona1]

This syntax is working now; resolving this issue:

yugabyte=#  create table test(id bigserial, b bigint);
CREATE TABLE
yugabyte=# create index on test((b));
CREATE INDEX
yugabyte=# \d+ test
                                               Table "public.test"
 Column |  Type  | Collation | Nullable |             Default              | Storage | Stats target | Description
--------+--------+-----------+----------+----------------------------------+---------+--------------+-------------
 id     | bigint |           | not null | nextval('test_id_seq'::regclass) | plain   |              |
 b      | bigint |           |          |                                  | plain   |              |
Indexes:
    "test_b_idx" lsm (b HASH)