MYSQL most recent time
Is there a way to grab the most recent time of day. If your data in the database is formatted like this 07:00AM and 08:00pm and 12:00pm. Sorta like max(). But for the time. In a My开发者_如何学Csql query.
Thanks Eric
It would be best to store it in another format rather than as text. Or at least store it in 24 hour format, then a simple sort would work. You can convert it to 12-hour format when you display the data to the user.
But assuming you can't change your database schema, try this:
SELECT *
FROM your_table
ORDER BY STR_TO_DATE(your_time, '%h:%i%p') DESC
LIMIT 1
Note that this won't be able to use an index to perform the sorting.
You should try STR_TO_DATE() instead if you're using a string. If your times are always formatted as hh:mmAMPM, you can use:
MAX(STR_TO_DATE(YourTimeField,'%h:%i%p'))
This converts your string to a time, without any need to split it up by substring or anything, so MySQL would then see 09:07AM as 09:07:00 and 02:35PM as 14:35:00, and then would easily be able to determine the MAX of it.
Assuming you are dealing with a DATETIME field in your MySQL, you can use this query to get the max time per day:
SELECT DATE(YourDateField), MAX(TIME(YourDateField)) FROM YourTable
GROUP BY DATE(YourDateField)
When you are dealing with a VARCHAR field, you can try a hack like this:
SELECT YourDateField, SUBSTRING(MAX(
CASE WHEN YourTimeField LIKE '%AM%' THEN '0' ELSE '1' END
+ REPLACE(YourTimeField, '12:', '00:')
), 2)
GROUP BY YourDateField
You can just sort.
select time_column from table order by time_column desc limit 1;
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