here is the "msg" table on mysql
sent_to customer msg read
------- -------- ------ -----
45 3 bla 0
34 4 bla 1
34 6 bla 0
45 3 bla 0
56 7 bla 1
45 8 bla 0
for example user whose id number is 45 logs in,
i want him to see this,
you have 2 unread msg to your "number 3" customer
you have 1 unread msg to your "number 8" customer
like a news feed
what query should i use for this ?
thx
You may want to use the following query.
SELECT CONCAT('You have ',
COUNT(`read`),
' unread msg to your number ',
customer,
' customer') AS news
FROM msg
WHERE `read` = '0' AND `sent_to` = '45'
GROUP BY customer;
Note that read
is a reserved word in MySQL, so you have to enclose it in backticks. ( Source )
Test case:
CREATE TABLE msg (
`sent_to` int,
`customer` int,
`msg` varchar(10),
`read` int
);
INSERT INTO msg VALUES(45, 3, 'bla', 0);
INSERT INTO msg VALUES(34, 4, 'bla', 1);
INSERT INTO msg VALUES(34, 6, 'bla', 0);
INSERT INTO msg VALUES(45, 3, 'bla', 0);
INSERT INTO msg VALUES(56, 7, 'bla', 1);
INSERT INTO msg VALUES(45, 8, 'bla', 0);
Query result:
+-------------------------------------------------+
| news |
+-------------------------------------------------+
| You have 2 unread msg to your number 3 customer |
| You have 1 unread msg to your number 8 customer |
+-------------------------------------------------+
2 rows in set (0.00 sec)
SELECT COUNT(read), customer FROM msg WHERE read = 0 AND sent_to = '45' GROUP BY customer;
select count(sent_to), customer
from msg
where read < 1
and sent_to = 45
group by customer
...
select count(*), customer from msg where read = 0 group by customer
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