> > The it will be MUCH faster to create secondary index which
> > is much smaller than heap and use values from it.
>
> Agreed. But this will add 16 bytes (2 xid + 2 cid) to size of btitems.
> Currently, total size of btitem for 2-int4 key index is 16 bytes =>
> new feature will double size of index and increase # of levels
> (obviously bad for mostly static tables).
>
> So, this feature should be *optional*...
yes. it definitely should.
> MVCC will not be affected by WAL currently. It's issue
> of storage manager, not WAL.
and where will the WAL sit ? can you explain it a bit ?
thanks devik