Do you mean to sum two columns in SQL - https://www.mysqltutorial.org/mysql-sum/ ? If you use Datalist JDBC Binder, you can use the SUM function to add two columns together and use CAST() to convert the string DB column value to numeric.

I would like to sum all records in one column.

I would like to use datalist that is already visible in in the datalist builder.

Do download the demo and training app Tutorial App: Datalist which have an example on how to "Display records with a sum total on the last row.". It involve the use of the UNION function in datalist SQL/JDBC.

It is still not what I need.

I need to sum the whole column in datalist not only data in a grid.

Could you clear it out? Thank you in advance.

Please try out Report Builder. In the List element, you can make use of "Footer Row" to compute summation of a column.

Please see Report Builder for more information.

Yes, but it sum only list or grid etc. I would like to sum datalist that is not visible.

Look below. Any help?