Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Drill, mail # dev - Exception while implementing drill trigonometric functions (For DRILL-219). Need tips.


Copy link to this message
-
Re: Exception while implementing drill trigonometric functions (For DRILL-219). Need tips.
Ted Dunning 2013-09-09, 20:09
Julian,

I encountered the same problem adding things like AVG.  Are aggregators
handled the same way (and in the same place)?
On Mon, Sep 9, 2013 at 12:30 PM, Julian Hyde <[EMAIL PROTECTED]> wrote:

> That error stack says that the SIN function is not known to Optiq's SQL
> validator. Optiq's validator is driven by a table of functions and
> operators, but Drill doesn't currently have a way to add to that table.
>
> Since SIN is a generally useful function, it should be built-in in Optiq.
> You could do that by modifying SqlStdOperatorTable and adding a field
> similar to the one that defines the SQRT operator:
>
>     public static final SqlFunction sqrtFunc >         new SqlFunction(
>             "SQRT",
>             SqlKind.OTHER_FUNCTION,
>             SqlTypeStrategies.rtiNullableDouble,
>             null,
>             SqlTypeStrategies.otcNumeric,
>             SqlFunctionCategory.Numeric);
>
> I believe the validation rules are identical for SQRT and SIN.
>
> However we should also add a mechanism to Drill to allow it to add its own
> functions (including user-defined functions) to Optiq's SQL validator on
> the fly.
>
> Julian
>
>