On 12 January 2016 at 11:49, Etsuro Fujita <fujita.ets...@lab.ntt.co.jp> wrote: > On 2016/01/12 20:36, Thom Brown wrote: >> >> On 8 January 2016 at 05:08, Etsuro Fujita <fujita.ets...@lab.ntt.co.jp> >> wrote: > > >>>> On 2016/01/06 20:37, Thom Brown wrote: >>>>> >>>>> I've run into an issue: >>>>> >>>>> *# UPDATE master_customers SET id = 22 WHERE id = 16 RETURNING >>>>> tableoid::regclass; >>>>> ERROR: >>>>> CONTEXT: Remote SQL command: UPDATE public.customers SET id = 22 >>>>> WHERE ((id = 16)) RETURNING NULL > > >>> While working on this, I noticed that the existing postgres_fdw system >>> shows >>> similar behavior, so I changed the subject. >>> >>> IIUC, the reason for that is when the local query specifies "RETURNING >>> tableoid::regclass", the FDW has fmstate->has_returning=false while the >>> remote query executed at ModifyTable has "RETURNING NULL", as shown in >>> the >>> above example; that would cause an abnormal exit in executing the remote >>> query in postgresExecForeignUpdate, since that the FDW would get >>> PGRES_TUPLES_OK as a result of the query while the FDW would think that >>> the >>> right result to get should be PGRES_COMMAND_OK, from the flag >>> fmstate->has_returning=false. > > >>> Attached is a patch to fix that. > > >> I can't apply this patch in tandem with FDW DML pushdown patch (either >> v2 or v3). > > > That patch is for fixing the similar issue in the existing postgres_fdw > system. So, please apply that patch without the DML pushdown patch. If > that patch is reasonable as a fix for the issue, I'll update the DML > pushdown patch (v3) on top of that patch.
The patch seems to work for me: Before: *# UPDATE master_customers SET id = 22 WHERE id = 1 RETURNING tableoid::regclass; ERROR: CONTEXT: Remote SQL command: UPDATE public.customers SET id = $2 WHERE ctid = $1 RETURNING NULL After: *# UPDATE master_customers SET id = 22 WHERE id = 1 RETURNING tableoid::regclass; tableoid ------------------ remote.customers (1 row) UPDATE 1 Thom -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers