On 2016/03/25 17:16, Etsuro Fujita wrote:
> The approach that we discussed would minimize the code for the FDW
> author to write, by providing the support functions you proposed. I'll
> post a patch for that early next week.
I added two helper functions: GetFdwScanTupleExtraData and
FillFdwScanTupleSysAttrs. The FDW author could use the former to get
info about system attributes other than ctids and oids in fdw_scan_tlist
during BeginForeignScan, and the latter to set values for these system
attributes during IterateForeignScan (InvalidTransactionId for
xmins/xmaxs, InvalidCommandId for cmins/cmaxs, and valid values for
tableoids). Attached is a proposed patch for that. I also slightly
simplified the changes to make_tuple_from_result_row and
conversion_error_callback made by the postgres_fdw join pushdown patch.
What do you think about that?
Best regards,
Etsuro Fujita