No worries. It’s President’s Day here in the US and none of us are supposed to be using our laptops. :)
> On Feb 20, 2017, at 12:05 PM, Kevin Risden <[email protected]> wrote: > > Ok I will log a JIRA case and try to add a test. Won't be able to get to it > till tonight when I'm back on my laptop. > > Kevin Risden > > On Mon, Feb 20, 2017 at 1:58 PM, Julian Hyde <[email protected]> wrote: > >> I do think it’s worth considering. Can you log a JIRA case please? >> >> Also, if you add a test — probably a few extra lines in RexProgramTest >> will suffice — I will accept your PR. I think it will be efficient enough. >> >> Julian >> >> >>> On Feb 19, 2017, at 7:14 PM, Kevin Risden <[email protected]> >> wrote: >>> >>> Thanks Julian. I looked in the existing rules but didn't come across the >>> ReduceExpressionsRule.FILTER_INSTANCE. Adding that rule to the planner >>> seems to do the same thing that I was trying to do in simplify. I don't >>> think there is any reason to change simplify. It was just the first way >> to >>> found to try to work around the issue I was facing. >>> >>> Would you still want a JIRA case logged since that would result in >> multiple >>> ways of doing the same thing? >>> >>> Kevin Risden >>> >>> On Sun, Feb 19, 2017 at 8:13 PM, Julian Hyde <[email protected] <mailto: >> [email protected]>> wrote: >>> >>>> We have support for this in planner rules -- I’m pretty sure that >>>> ReduceExpressionsRule.FILTER_INSTANCE will convert ‘where 1 = 0’ to >>>> ‘where false’, then PruneEmptyRules.FILTER_INSTANCE will make the >> Filter >>>> disappear altogether — but arguably it could happen in RexUtil.simplify >>>> also. >>>> >>>> The purpose of RexUtil.simplify is to simplify (only) patterns that are >>>> commonly occurring, easy to recognize, and will produce a quick win in >>>> terms of the size of the RelNode/RexNode tree. I don’t know yet whether >>>> this passes that threshold. Can you log a JIRA case for this and we can >>>> discuss further? >>>> >>>> By the way, https://issues.apache.org/jira/browse/CALCITE-1638 < >>>> https://issues.apache.org/jira/browse/CALCITE-1638 < >> https://issues.apache.org/jira/browse/CALCITE-1638>> is related. It >>>> changed the result of a test that was doing ‘where 1 = 1’. >>>> >>>> Julian >>>> >>>> >>>> >>>> >>>>> On Feb 19, 2017, at 2:03 PM, Kevin Risden <[email protected]> >>>> wrote: >>>>> >>>>> While working on Solr and Calcite integration, I found that there is a >>>> case >>>>> where some tools issue a sql query like "where 1 = 0" just to get >>>> metadata >>>>> information back. Spark SQL is one of the ones that does this. >>>>> >>>>> Calcite doesn't seem to optimize away the literal comparison literal >> case >>>>> with RexUtil.simplify. In my understanding any literal comparison >> literal >>>>> results in a simple TRUE/FALSE result. >>>>> >>>>> I'm not sure this is valid in the general case, but I put together a >>>> simple >>>>> example of doing this on the RexUtil simplifyCall. >>>>> >>>>> https://github.com/apache/calcite/pull/376 >>>>> >>>>> I would love to hear any feedback related to this. I need to run >> through >>>>> the full Calcite test suite, but wondering if this is even viable. >>>>> >>>>> Thanks! >>>>> >>>>> Kevin Risden >> >>
