"Ed L." <pgsql(at)bluepolka(dot)net> writes:
> create table pg_xlog (
> xid int4 unique not null,
> recno int8 unique not null,
> );
> -- recno = (XLogRecPtr.xlogid) << 32) + XLogRecPtr.xrecoff
> This would map transaction IDs to WAL log record numbers. It seems
> straight-forward to get the right data into this table.
... except that once a transaction has committed, it can't go around
making more database entries. You can only modify the DB within a
transaction.
regards, tom lane