Thanks John and Dominique! Unfortunately our column has a keyword index, so we are unable to use "in" queries. We will try to balance our parentheses.
Have either of you had success increasing the stack size? I tried using ulimit and setrlimit, but neither seemed to work. John - Have you considered changing the methods that operate on the parse tree to be iterative rather than recursive? I started looking at ibis::qExpr::simplify and I noticed two challenges: 1. ibis::qExpr::simplify requires post-order traversal, which is somewhat unnatural to implement iteratively 2. There are possibly many other methods which would need to be modified On 9/5/13 5:17 PM, "K. John Wu" <[email protected]> wrote: >Hi, Dominique and Steve, > >If your long list of ORs are most related to a single column (or a >small number of columns), then it is possible to convert them into an >expression of the form > >column_name IN (list_of_strings_or_numbers ) > >The list in the parentheses has to be either a list of numbers of a >list of strings (a mixture will be treated as a list of strings). > >Hope this helps. > >John > >PS: more information about expressions of a where clause is available at > >http://lbl.gov/~kwu/fastbit/doc/html/classibis_1_1whereClause.html > > >On 9/5/13 3:39 PM, Prunier, Dominique wrote: >> Steve, >> >> >> >> We faced the same issue and we worked around that by carefully >> balancing the big OR with parenthesis so that you don¹t go deeper that >> log2(OR count). >> >> >> >> Hope this helps ! >> >> >> >> Thanks, >> >> >> >> *From:*[email protected] >> [mailto:[email protected]] *On Behalf Of *Enns, >>Steven >> *Sent:* Thursday, September 05, 2013 6:16 PM >> *To:* FastBit Users >> *Subject:* [FastBit-users] stack overflow on large queries >> >> >> >> Hi John, >> >> >> >> I am running a query of 2140 OR clauses and observing segmentation >> fault in ibis::qExpr::simplify(ibis::qExpr*&) at recursive depth of >> 1087. Could you help us debug this? >> >> >> >> Thanks! >> >> Steve >> >> >> >> >> >> >> >> >> >> _______________________________________________ >> FastBit-users mailing list >> [email protected] >> https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users >> >_______________________________________________ >FastBit-users mailing list >[email protected] >https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users _______________________________________________ FastBit-users mailing list [email protected] https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
