How to create sql query where string field is empty ?

To create a SQL query where a string field is empty, you can use the IS NULL or ='' conditions. Here's an example query using both conditions:

SELECT * FROM your_table_name
WHERE your_string_field IS NULL
OR your_string_field = '';

This query will return all rows from your_table_name where your_string_field is either null or an empty string. Replace your_table_name and your_string_field with your actual table and column names.