Rod Taylor <rbt(at)rbt(dot)ca> writes:
> - alter table structure
> - Add all new constraints (without confirming their correctness at that
> time)
> - update table contents via an SPI call to UPDATE WHERE <column> IS NULL
> The where clause would avoid issues with inherited data being
> overwritten when the child tables are updated.
But it creates issues with failing to check the new constraints at those
same child rows.
regards, tom lane