On Fri, 2023-03-31 at 10:35 -0700, Siddharth Jain wrote: > Is following correct? > > when a PK is created on (X,Y) on the parent table what happens internally is that the > command is run individually on each of the child tables. nothing more. nothing less. If you are talking about inheritance, no. Creating a constraint on the parent table has no effect on a child table. If you are talking about partitioning: If you create a primary key on the partitioned table, that will be implemented by a partitioned index. That partitioned index consists of a unique index for each partition. So I guess that is more or less what you mean. There are some differences between a primary key on the partitioned table and a unique index on each partition: - the primary key is a constraint, so it can be the target of a foreign key - the primary key will force a unique index on each new partition - the primary key keeps you from dropping the unique index on the partitions Yours, Laurenz Albe
