Atri Sharma <atri.jiit@gmail.com> writes:
> On Sat, Oct 6, 2012 at 3:45 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Atri Sharma <atri.jiit@gmail.com> writes:
>>> I am trying to identify foreign scans uniquely.
>> What do you mean by "identify"? What are you trying to accomplish,
>> and in what context?
> I am trying to identify the situation where a query has multiple
> foreign scans.In that case,I need to check whether the current scan is
> the same as a previous scan or not.If not,then I think it means that
> multiple scans are in progress on the same backend.
Well, if you search the plan tree and find more than one ForeignScan
node, it means there's more than one foreign scan. It doesn't seem to
me to be very complicated. Now, if you're wondering whether they
reference the same server or not, that's a bit harder. I guess you
could look at the RTEs, fetch the foreign-table data for each FT
relation OID, and see if the same server is referenced.
regards, tom lane