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From Arina Yelchiyeva <arina.yelchiy...@gmail.com>
Subject Re: How to create a UDF with variable length parameters ?
Date Tue, 17 Jan 2017 17:31:37 GMT
You can create several functions with the same name but with different
parameters types and / or quantity.

Example:
*bool_or* [1] function can have different input parameter: BitHolder or
NullableBitHolder
*maxdir* [2] can have one or two input parameters (but code is in template
you have to build Drill project to see generated DirectoryExplorers.class).


[1] https://github.com/apache/drill/blob/5a4ad2a88331dfe7561
ee76fc87e882afe170681/exec/java-exec/src/main/java/org/
apache/drill/exec/expr/fn/impl/BooleanAggrFunctions.java
[2] https://github.com/apache/drill/blob/1e6fa00cd4b0b1db416
14749f6d12c03f0ca7990/exec/java-exec/src/main/codegen/
templates/DirectoryExplorers.java

On Tue, Jan 17, 2017 at 6:39 PM, Muhammad Gelbana <m.gelbana@gmail.com>
wrote:

> Is there a way to create a UDF that supports typically 1 or more parameters
> ? Parameters may be columns, literals or NULLs and the return may be NULL
> or a value.
>
> It would be still possible to overload such a UDF by declaring one with a
> different type of variables, correct ?
>
> *---------------------*
> *Muhammad Gelbana*
> http://www.linkedin.com/in/mgelbana
>

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