I am using the following statement

ALTER TABLE Tab1 ALTER COLUMN IdCol RESTART WITH 1

to reset an identity column.

PostgreSQL locks the entire table in exclusive mode whenever it processes the ALTER TABLE statement. Hence ALTER TABLE cannot be executed concurrently with other operations on the same table.

Does the above statement in DB2 lock the whole table? I would like to know more about the types of locks that are implicitly placed for SQL statements. Is there any documentation available on this?

What is the authorization level required to run ALTER TABLE statement?