sql: database name inconsistent in crdb_internal.create_statements table select statement

[RichardJCai]

The database_name for the following SELECT statements differ although the returned row should be the same.
Tested with descriptor_name pg_views descriptor_id 4294967174

[email protected]:26257/movr> select database_name, descriptor_name, descriptor_id from movr.crdb_internal.create_statements where descriptor_id = 4294967174;
  database_name | descriptor_name | descriptor_id
----------------+-----------------+----------------
  movr          | pg_views        |    4294967174
(1 row)

Time: 2ms total (execution 2ms / network 0ms)

[email protected]:26257/movr> select database_name, descriptor_name, descriptor_id from movr.crdb_internal.create_statements where descriptor_name = 'pg_views';
  database_name | descriptor_name | descriptor_id
----------------+-----------------+----------------
  NULL          | pg_views        |    4294967174
(1 row)

Time: 97ms total (execution 96ms / network 0ms)

[email protected]:26257/movr>

It may be worth noting that descriptor_id is indexed and descriptor_name is not

[blathers-crl]

Hi @rafiss, please add branch-* labels to identify which branch(es) this release-blocker affects.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is otan.}

[RichardJCai]

Did some digging on this, turns out the reason the DB is nil is because we hardcode a nil DatabaseDescriptor at https://github.com/cockroachdb/cockroach/blob/master/pkg/sql/information_schema.go#L2132