Re: does database shut down cleanly when WAL device fails?

Brandon Craig Rhodes  writes:
>       And the disputed point:

>         - If the drive holding the WAL fails, then the database engine
>           will shut down cleanly by writing everything in RAM out to
>           the real database tables, and no data will be lost.

Whoever claimed that has no familiarity with the code at all, and no
understanding of the basic WAL rule: write to the log BEFORE you write
data.

In point of fact, loss of the WAL drive will mean a database PANIC stop
and probably a corrupt data area afterwards, since there'd be no
guarantee that related page updates had all made it to disk.

			regards, tom lane