Re: The exact timing at which CHECK constraints are checked

Takahiro Noda <noda.takahiro.47m@st.kyoto-u.ac.jp> writes:
> I'm new to PostgreSQL and having been learning SQL. I'm uncertain
> about the exact timing at which CHECK constraints are checked.

They're checked at the instant that a row is inserted or updated.
If you really need a deferred check, you'll need to build it yourself
using an AFTER ROW trigger.

            regards, tom lane