I'm adding a dataset with a column for zip codes. The leading zeros are being removed when the data is uploaded, is there a way to prevent this/change the formatting for that column?
If you can, import the data as a string instead of an integer.
If you are unable to change how the data is coming in as @ST_-Superman-_ suggests, you can use the LPAD() function to add the leading zero, when necessary. You can do this in Analyzer by creating a beast mode, or in Magic ETL using the formula tile. It would look like this:
LPAD(zip,5,'0')
This will add a zero to the front of the string if it is less than 5 characters to make it 5 characters long.