Re: currtid_byreloid and currtid_byrelname

Heikki Linnakangas <heikki@enterprisedb.com> writes:
> In utils/adt/tid.c, there's two mysterious functions with no comments, 
> and no-one calling them inside backend code AFAICT: currtid_byreloid and 
> currtid_byrelname. What do they do/did?

IIRC, the ODBC driver uses them, or once did, to deal with
concurrent-update situations --- it wants to be able to find the
currently committed version of a row it saw as valid earlier in the
transaction.  I think it's sort of a client-side version of the
EvalPlanQual stuff.  Hiroshi probably remembers more.
        regards, tom lane