Get the latest date from grouped MySQL data

Question

I have the following data in my database:

|NO | model | date     | 
+---+-------+----------+
|1  | bee   |2011-12-01|
|2  | bee   |2011-12-05|
|3  | bee   |2011-12-12|
|4  | tar   |2011-12-13|

I want to get the latest date of each model group:

| model | date     | 
+-------+----------+
| bee   |2011-12-12|
| tar   |2011-12-13|

I tried:

SELECT model, date 
FROM doc
WHERE date ........????? //what is the next?
GROUP BY model

Answer 1

Are you looking for the max date for each model?

SELECT model, max(date) FROM doc
GROUP BY model

If you're looking for all models matching the max date of the entire table...

SELECT model, date FROM doc
WHERE date IN (SELECT max(date) FROM doc)

[--- Added ---]

For those who want to display details from every record matching the latest date within each model group (not summary data, as asked for in the OP):

SELECT d.model, d.date, d.color, d.etc FROM doc d
WHERE d.date IN (SELECT max(d2.date) FROM doc d2 WHERE d2.model=d.model)

MySQL 8.0 and newer supports the OVER clause, producing the same results a bit faster for larger data sets.

SELECT model, date, color, etc FROM (SELECT model, date, color, etc, 
  max(date) OVER (PARTITION BY model) max_date FROM doc) predoc 
WHERE date=max_date;

Answer 2

You can try using max() in subquery, something like this :

SELECT model, date  
FROM doc 
WHERE date in (SELECT MAX(date) from doc GROUP BY model);

Answer 3

Subquery giving dates. We are not linking with the model. So below query solves the problem.

If there are duplicate dates/model can be avoided by the following query.

select t.model, t.date
from doc t
inner join (select model, max(date) as MaxDate from doc  group by model)
tm on t.model = tm.model and t.date = tm.MaxDate

Answer 4

try this:

SELECT model, date
FROM doc
WHERE date = (SELECT MAX(date)
FROM doc GROUP BY model LIMIT 0, 1)
GROUP BY model

Answer 5

Using max(date) didn't solve my problem as there is no assurance that other columns will be from the same row as the max(date) is. Instead of that this one solved my problem and sorted group by in a correct order and values of other columns are from the same row as the max date is:

SELECT model, date 
FROM (SELECT * FROM doc ORDER BY date DESC) as sortedTable
GROUP BY model

Answer 6

This should work:

SELECT model, date FROM doc GROUP BY model ORDER BY date DESC

It just sort the dates from last to first and by grouping it only grabs the first one.

Answer 7

为什么不使用这个？

SELECT model, date FROM doc ORDER BY date DESC LIMIT 1