How to convert 'str' to 'int' in [custom question]?

I want to convert 'str' to 'int',
but I failed.
'str' + 0...--'str'...function: convert, cast...

I am helpless...

How to use the result from custom question in native query?

Hi @JayceS
These are the functions available in Metabase:
There's currently no casting/convert functions available.

Yes, I have read all the doc but no use...

@JayceS If you have read the documentation, then you would see that there's no cast function. You would have to do such conversion in SQL or with a database View.