How do I check if a column is empty or null in MySQL?

I have a column in a table which might contain null or empty values. How do I check if a column is empty or null in the rows present in a table?

(e.g. null or '' or '  ' or '      ' and ...)

Answer

This will select all rows where some_col is NULL or '' (empty string)

SELECT * FROM table WHERE some_col IS NULL OR some_col = '';