How do I change all empty strings to NULL in a table?

Question

I have a legacy table with about 100 columns (90% nullable). In those 90 columns I want to remove all empty strings and set them to null. I know I can:

updat         


        

Answer 1

Hammerite's answer is good but you can also replace CASE statements with IFs.

UPDATE
    TableName
SET
    column01 = IF(column01 = '', NULL, column01),
    column02 = IF(column02 = '', NULL, column02),
    column03 = IF(column03 = '', NULL, column03),
    ...,
    column99 = IF(column99 = '', NULL, column99)