One of the benefit is that instead of LLM blindly advising you to do

> ALTER TABLE customers ALTER COLUMN email SET NOT NULL;

it can advise you to

-- Step 1: backfill NULLs UPDATE customers SET email = 'unknown-' || id || '@example.com' WHERE email IS NULL;

-- Step 2: add constraint without full table scan ALTER TABLE customers ADD CONSTRAINT customers_email_not_null CHECK (email IS NOT NULL) NOT VALID;

-- Step 3: validate in the background with a weaker lock ALTER TABLE customers VALIDATE CONSTRAINT customers_email_not_null;