How do I set a column type?

To set a column to a different type, you can use the make_col verb in OPAL. Here's the syntax:

make_col new_column_name:new_data_type(existing_column)

Replace new_column_name with the desired name for the new column and new_data_type with the desired data type. existing_column should be the name of the column you want to convert.

For example, if you want to set a column named age to be of type int64, you would use the following OPAL expression:

make_col age:int64(age)

You can also click the Down arrow at the top of the column and click the Convert button from the dropdown menu that appears.