Count users from table 2 in request to table 1
I have table with positions
tbl_positions
id position
1 Driver
2 Lobby
3 S开发者_JS百科upport
4 Constructor
and in other table i have users
tbl_workers
id name position status
1 John 2 3
2 Mike 3 2
3 Kate 2 3
4 Andy 1 0
i do request of positions
Without status I select everything with this query .
SELECT p.id, p.position, count(*) FROM tbl_positions as p
inner join tbl_workers as w on w.position=p.id
group by p.id, p.position
But now i need output same query but also considers status, status 2=booked status, 3=placed. I need output like this in single query.
Position booked placed
Driver 0 0
Lobby 0 2
Support 1 0
Constructor 0 0
I tried add WHERE tbl_workers.status IN (2)
for booked and WHERE tbl_workers.status IN (3)
for placed and it works in two queries, but no luck joining this into one query
Try this:
SELECT p.id,
p.position,
SUM(CASE w.Status WHEN 2 THEN 1 ELSE 0 END) AS booked,
SUM(CASE w.Status WHEN 3 THEN 1 ELSE 0 END) AS placed
FROM tbl_positions AS p LEFT JOIN tbl_workers AS w
ON w.position=p.id
GROUP BY p.id, p.position
Although you can do this with a single SQL query, it may be more straightforward to handle this using PHP.
Use your current query and add status
to the GROUP BY
.
SELECT p.id, p.position, w.status, count(*) FROM tbl_positions as p
inner join tbl_workers as w on w.position=p.id
group by p.id, p.position, w.status
You'll get a result set like this:
position status count
Driver 2 0
Lobby 2 0
Support 2 1
Constructor 2 0
Driver 3 0
Lobby 3 2
Support 3 0
Constructor 3 0
Use PHP to logically determine 2 = booked
and 3 = placed
.
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