How to Return a Value Even When No Row Is Found in MySQL?
Published on 2024-11-16
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Returning a Value Even When No Row Is Found
In MySQL, fetching a value for a given ID may return an empty resultset if the ID doesn't exist. To always retrieve a value, you can leverage the IFNULL() function.
The IFNULL() function takes two arguments: the expression to evaluate and the value to return if the expression is null. In the example provided, you want to return the field1 if it exists, or 'not found' if it doesn't.
You can apply this function to the entire query using the following syntax:
SELECT IFNULL( (SELECT field1 FROM table WHERE id = 123 LIMIT 1) ,'not found');
This single query statement avoids running the same subquery twice, as in the original solution. It efficiently returns the desired value, ensuring that your code always has a response.
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