Hi Hanada-san, > Please examine attached v2 patch (note that is should be applied onto > latest dblink_fdw_validator patch).
I've reviewed your patch quickly. I noticed that the patch has been created in a slightly different way from the guidelines: http://www.postgresql.org/docs/devel/static/fdw-planning.html The guidelines say the following, but the patch identifies the clauses in baserel->baserestrictinfo in GetForeignRelSize, not GetForeignPaths. Also, it has been implemented so that most sub_expressions are evaluated at the remote end, not the local end, though I'm missing something. For postgresql_fdw to be a good reference for FDW developers, ISTM it would be better that it be consistent with the guidelines. I think it would be needed to update the following document or redesign the function to be consistent with the following document. As an example, the FDW might identify some restriction clauses of the form foreign_variable= sub_expression, which it determines can be executed on the remote server given the locally-evaluated value of the sub_expression. The actual identification of such a clause should happen during GetForeignPaths, since it would affect the cost estimate for the path. Thanks, Best regards, Etsuro Fujita -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
