How do I create a UDF in datafusion rust?

[chauhanVritul]

I want to make a UDF similar to array_contains(), since it is not supported by datafusion.
Consider a table like this:

col_1 | col_2
"one" | [ "123", "234", "345"]
"two" | [ "987", "876", "123"]

I only want the columns containing "123". So the SQL query is like: SELECT * FROM table WHERE array_contain(col_2, "123")

The example provided is good but am unable to give it a valid return type.

[alamb]

Hi @chauhanVritul !

The return type of this function should be Boolean, right? And the input type should be ListArray?

I assume the example you refer to is https://github.com/apache/arrow-datafusion/blob/41b4e491663029f653e491b110d0b5e74d08a0b6/datafusion-examples/examples/simple_udf.rs

Would it be possible to paste in what you have tried so far?

[Jefffrey]

We have array_has function now.

And for reference we do have a guide on creating UDFs on the site now