On Thu, 1 Apr 2021 at 15:39, Bruce Momjian <bruce@momjian.us> wrote:
On Thu, Apr 1, 2021 at 11:24:48AM -0400, Dave Cramer wrote: > CTE's don't change the isolation level. I'm not sure what you are getting at > here ?
I think what he/she means here is that all queries in a CTE use a single snapshot, meaning you don't see changes by commits that happen between queries that are part of the same CTE. If you were running the queries separately in read committed mode, you would see those changes, but you would not see them in repeatable read or serializable transaction mode.
OK, that makes sense, but I think it is wrong minded to think that this absolves one of taking isolation into account.
When you make the first read you will still have to deal with all of the isolation issues