If you want to sort the list by a certain order, such as a list of numbers from the beginning of 4,5,1, and then in ascending order, you can create a sort order by IF statement rule with additional columns for sorting:
SELECT id, -- additional columns for sorting IF(id=4, 1, 0) c1, IF(id=5, 1, 0) c2, IF(id=1, 1, 0) c3 FROM test WHERE id IN(1,2,3,4,5,6,7,8,9,10) -- now sort by additional columns descending and other ascending ORDER BY c1 DESC, c2 DESC, c3 DESC, id ASC
Query result:
id c1 c2 c3 4 1 0 0 5 0 1 0 1 0 0 1 6 0 0 0 7 0 0 0 8 0 0 0 9 0 0 0 10 0 0 0
In this example, the statement condition returns 1 or 0, since 0 is above 1, so do a reverse sort by descending order, then the values in additional columns will be first. MySQL statements can be used immediately in the sorting, then the query is changed as follows:
SELECT id FROM test WHERE id IN(1,2,3,4,5,6,7,8,9,10) -- sort order by conditions ORDER BY IF(id=4, 1, 0) DESC, IF(id=5, 1, 0) DESC, IF(id=1, 1, 0) DESC, id ASC
Query result:
id 4 5 1 6 7 8 9 10
Since the IF statement return 0 or 1, it can be replaced by equal operator, so query would be:
SELECT id FROM test WHERE id IN(1,2,3,4,5,6,7,8,9,10) -- sort order by equal operators ORDER BY id=4 DESC, id=5 DESC, id=1 DESC, id ASC
Query result:
id 4 5 1 6 7 8 9 10
Instead IF statement can use CASE statement:
SELECT id
FROM test
WHERE id IN(1,2,3,4,5,6,7,8,9,10)
ORDER BY
-- sort by case
CASE id
WHEN 4 THEN 1
WHEN 5 THEN 2
WHEN 1 THEN 3
ELSE 4
END ASC
Query result:
id 4 5 1 6 7 8 9 10
