'IF EXISTS ELSE?

How would one fix this query?

IF EXISTS (SELECT * FROM links WHERE age='10')

SELECT * FROM links WHERE age = '10' ORDER BY

ELSE

SELECT * FROM links ORDER BY

So if a link exists which is 10 days exactly then it would be displayed otherwise it would be random.

mysql


Solution 1:[1]

You have two different queries - use a union:

 SELECT *
 FROM links
 WHERE age = '10'
 UNION ALL
 SELECT *
 FROM links
 WHERE NOT EXISTS (SELECT * FROM links WHERE age='10')
 ORDER BT RAND()

Solution 2:[2]

I suppose you could write:

SELECT *
  FROM links
 WHERE age = '10'
    OR NOT EXISTS
        ( SELECT 1
            FROM links
           WHERE age = '10'
        )
 ORDER
    BY RAND()
 LIMIT 1
;

. . . but I'm not sure how well it will perform. It may make more sense to just run the query with WHERE age = '10', and then run the other query only if the first returns no results.

Sources

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Source: Stack Overflow

Solution Source
Solution 1 Bohemian
Solution 2

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