如何在MySQL中获取colName为TimeStamp类型的max（colName）值

Question

I am having following table structure and having the following Data in this table Now I want to query in such a way so that I can have values of all the columns + the value of max(currenttime) for a particular game_id.

i am running the following query SELECT _id, game_id, inning_id, scoretype, oponentonescore, oponenttwoscore, currenttime, MAX( currenttime ) AS latest FROM game_scores WHERE game_id = '2268'

and as a result i am getting only one row as in the following result But i want want all rows matching the criteria(ie game id 2268)

How to compose Query to achieve this?

Thanks in advance

Answer 1

Your MAX() is an aggregate type function and gets one value for multiple rows.

So remove it and use something like this with PHP...

$maxTime = 0;

foreach($rows as $row) {
   $maxTime = max($maxTime, strtotime($row['currenttime']));
}

...or run another query, though the above should be sufficient...

SELECT MAX(`currenttime`) AS `latest`
  FROM `game_scores`
 WHERE `game_id` = '2268'

Formatted in your convenience OMG Ponies style .

Answer 2

i'm sorry, i haven't actually tested this, but maybe something like this would do the trick:

SELECT
    _id,
    game_id,
    inning_id,
    scoretype,
    oponentonescore,
    oponenttwoscore,
    currenttime,
    latest
FROM
    game_scores
JOIN (
    SELECT
        MAX(currenttime) AS latest
    FROM
        game_scores
    WHERE
        game_id = '2268'
) AS latest_calculation
WHERE game_id = '2268';

although this solution is heavier on the database than it is heavy on the application to figure it out after the query is back from the database (like alex suggested).

Answer 3

Something on the lines of this query would do the required. NOT TESTED.

 SELECT _id, game_id, inning_id, scoretype, oponentonescore, oponenttwoscore,
    currenttime,maxtime from game_scores OUTER join (SELECT _id,MAX(currenttime)
    as maxtime from game_scores) as t on t._id = game_scores._id  where game_id = '2268';