Mysql query inner join two tables with group by last ID - mysql

Question

I'm using two tables in the database:
The "members" table:
id | name
-----------------------
1 | John
2 | Mike
3 | Jane
4 | Marry
The "messages" table:
message_id | text | from | to
---------------------------------------------
1 | text 1 | 1 | 2
2 | text 2 | 1 | 3
3 | text 3 | 1 | 4
4 | text 4 | 2 | 1
5 | text 5 | 1 | 2
I need to get as a result grouped messages sent by a specific user, sorted by the last message sent and count the total number of sent messages to specific user.
My current mysql query looks:
SELECT max(messages.message_id) as max_mess, messages.from, messages.to, members.name, messages.text
FROM messages INNER JOIN members on members.id = messages.to
WHERE messages.from = '1'
GROUP BY messages.from
ORDER BY max_mess DESC
Required result should look like:
max_mess | from | to | name | text | total_messages
--------------------------------------------------------------------
5 | 1 | 2 | Mike | text 5 | 3
3 | 1 | 4 | Marry | text 3 | 1
2 | 1 | 3 | Jane | text 2 | 1
Is it possible to do that using only one mysql query and what should be changed in the current query?

Answer 1

You can use one of the following solutions:
solution #1 (using a additional JOIN):
SELECT
m1.max_mess,
m1.from,
m1.to,
m1.name,
m2.text,
m1.total_messages
FROM (
SELECT
MAX(message_id) AS max_mess,
messages.from,
messages.to,
members.name,
COUNT(message_id) AS total_messages
FROM messages INNER JOIN members ON members.id = messages.to
WHERE messages.from = 1
GROUP BY messages.from, messages.to
) m1 LEFT JOIN messages m2 ON m1.max_mess = m2.message_id
ORDER BY m1.max_mess DESC;
demo: http://sqlfiddle.com/#!9/7c73b6/1/0
Note: This solution should be faster than the second solution. You can find more details on the following answer on StackOverflow: JOIN vs. Sub-Query.
solution #2 (using a sub-select):
SELECT
MAX(message_id) AS max_mess,
m1.from,
m1.to,
members.name,
(SELECT messages.text FROM messages WHERE message_id = MAX(m1.message_id)) as text,
COUNT(message_id) AS total_messages
FROM messages m1 INNER JOIN members ON members.id = m1.to
WHERE m1.from = 1
GROUP BY m1.from, m1.to
ORDER BY max_mess DESC;
demo: http://sqlfiddle.com/#!9/7c73b6/2/0

Answer 2

This is one query. If you want to remove the JOIN statement then you should use
SELECT max(messages.message_id) as max_mess, messages.from, messages.to, members.name, messages.text
FROM messages, members
WHERE messages.from = '1' AND members.id = messages.to
GROUP BY messages.from
ORDER BY max_mess DESC

Answer 3

i think you are searching for this:
SELECT MAX(messages.message_id) AS max_mess, messages.from, messages.to, members.name, messages.text,, SUM(`from`) total_messages
FROM messages INNER JOIN members ON members.id = messages.to
WHERE messages.from = '1'
GROUP BY messages.from,messages.to
ORDER BY max_mess DESC;