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mysql - Return Default value if no row found

I'm building query to search multiple rows from database like

SELECT 
  * 
FROM
  table1 
WHERE col1 = '012311' 
  OR col1 = '0123631' 
  OR col1 = '091233' 
  OR col1 = '092111' 

Here it returns first 3 values because they are present in the table but it returns nothing for last one because it's not in table. So how can I set my default value in the query if no row is found for that value?

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1 Answer

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by (71.8m points)

There are several approaches, which depend on the dataset. Here's one way:

SELECT *, 
IFNULL(
    ( SELECT col1 FROM table1 
        WHERE col1 IN ('012311','0123631','091233','092111') 
    ),
    'some_value'
) AS my_col1
FROM table1;

Not neccessarily copy+paste, you will have to adjust for your specific case.


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