# postgres/squawk > Checks every migration for changes that lock or rewrite a table, or break the running application. Checks every migration for changes that lock or rewrite a table, or break the running application. Part of the [`postgres`](/reference/configurations/postgres/) configuration, at the `recommended` [level](/start/concepts/#levels). It runs at the `commit` [stage](/start/concepts/#stage), per file. It runs squawk. ## Why A migration that takes an exclusive lock on a large table stops the application for as long as it runs. ## What to do Follow the advice squawk prints for the rule. Turn one rule off with `gspot ignore postgres/squawk --rule --reason ""`. ## Example A migration that adds a constraint with a full table scan reports a finding. Create the constraint first, and validate it in a separate migration. ## Turn it off Turn it off for some files, or one of its lint rules, with a reason: ```shell gspot ignore postgres/squawk --paths "" --reason "" gspot ignore postgres/squawk --rule --reason "" ```