MySQL order rank as a column
I have a MySQL query that selects data from multiple tables and then orders the results based on some arbitrary criteria as below:
SELECT [columns] FROM (
SELECT *开发者_StackOverflow中文版, COUNT(*) as `matches`
FROM [table1]
JOIN [table2] USING (id)
JOIN [table3] USING (id)
WHERE [criteria]
GROUP BY `id`
ORDER BY `matches` DESC
) AS `grouped`
ORDER BY (
(CASE WHEN [1st rank criteria] THEN 3 ELSE 0 END) +
(CASE WHEN [2nd rank criteria] THEN 2 ELSE 0 END) +
(CASE WHEN [3rd tank criteria] THEN 1 ELSE 0 END)
) DESC
LIMIT 100
This works fine, but my question is: can I have the ranking score displayed as a column? I've looked at trying to use variables, but I'm quite new to SQL so all this is a bit beyond me.
Sorry if this is an obvious question, but many thanks in advance for your time and assistance.
Try this:
SELECT [columns],
(
(CASE WHEN [1st rank criteria] THEN 3 ELSE 0 END) +
(CASE WHEN [2nd rank criteria] THEN 2 ELSE 0 END) +
(CASE WHEN [3rd tank criteria] THEN 1 ELSE 0 END)
) AS MyRank
FROM (
SELECT *, COUNT(*) as `matches`
FROM [table1]
JOIN [table2] USING (id)
JOIN [table3] USING (id)
WHERE [criteria]
GROUP BY `id`
ORDER BY `matches` DESC
) AS `grouped`
ORDER BY MyRank DESC
LIMIT 100;
put it in the select
((CASE WHEN [1st rank criteria] THEN 3 ELSE 0 END) +
(CASE WHEN [2nd rank criteria] THEN 2 ELSE 0 END) +
(CASE WHEN [3rd tank criteria] THEN 1 ELSE 0 END)) as ranking
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