Sort table by Integer values - bind values as Integer

Hi everyone,
I want to sort some column, but the values are String type. How can I bind values into the table by their real types, like integer; then sort the column. If the values are string I get sorting like 1,11,2,22,3.....
So I have 2 questions:
1. How to bind values by their real type (Int, DateTime...)
2. How to sort column, if the values are string and I need them to be Int.

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