HI im running socialengine3 and need optimization on the a custom Mutual friends query.
Its currently taking 15 seconds to execute
Friends table
friend_id
friend_user_id1
friend_user_id2
friend_status
friend_type
users
user_id
Edited
I have converted in into exists and still its now executing in 20 seconds.
below is the updated query.
SELECT friendlist.friend_user_id2, se_users.username, se_users.id, se_users.image, se_users.name, se_users.surname, count( * ) AS mutral_friends
FROM `se_friends` friendlist
INNER JOIN `users` se_users ON friendlist.friend_user_id2 = `se_users`.id
WHERE EXISTS (
SELECT se.friend_user_id2
FROM se_friends se
WHERE se.friend_user_id1 = '105012'
AND se.friend_status = '1'
AND se.friend_user_id2 = friendlist.friend_user_id1
) AND NOT EXISTS (
SELECT se1.friend_user_id2
FROM `se_friends` se1
WHERE se1.friend_user_id1 = '105012'
AND friendlist.friend_user_id2 = se1.friend_user_id2
)
AND NOT (
friendlist.friend_user_id2 = '105012'
)
AND friendlist.friend_status = '1'
GROUP BY friendlist.friend_user_id2, se_users.username, se_users.id, se_users.image, se_users.name, se_users.surname
ORDER BY mutral_friends DESC
LIMIT 0 , 20
Orignal query
SELECT DISTINCT `se_friends`.friend_user_id2, se_users.username, se_users.id, se_users.image, se_users.name, se_users.surname, count(*) as mutral_friends
FROM `se_friends`
INNER JOIN `users` se_users` ON `se_friends`.friend_user_id2=`se_users`.id
WHERE
(se_friends.friend_user_id1 <> '30355' or se_friends.friend_user_id2 <> '30355') AND
se_friends.friend_user_id1 IN
(SELECT se_friends.friend_user_id2
FROM `se_friends`
WHERE se_friends.friend_user_id1='".$user_id."' AND se_friends.friend_status='1')
AND `se_friends`.friend_user_id2 NOT IN
(SELECT se_friends.friend_user_id2
FROM `se_friends`
WHERE se_friends.friend_user_id1='".$user_id."'
)
AND NOT(se_friends.friend_user_id2='".$user_id."') AND se_friends.friend_status='1'
GROUP BY `se_friends`.friend_user_id2, se_users.username, se_users.id, se_users.image, se_users.name, se_users.surname
ORDER BY mutral_friends DESC
LIMIT 0, 20
IN is very expensive operation.
try to replace it with EXISTS. eg
select * from table where user_id in (select user_id from users where active='A')
and
select * from table t where exists (select user_id from users u where t.user_id = u.user_id and u.active='A')
if it won't be helpful, it's better to look at execution plan
Related
I have two requests
UPDATE :
I need to do something like that :
SELECT poste_nom, ups_type_contrat,
(SELECT `entpro_date`
FROM ENT_PRO
WHERE entpro_user_id = 2
ORDER BY `entpro_id` DESC
LIMIT 1) ,
serv_nom,
serv_id_resp,
user_credit_cpf,
user_indice_salarial,
FLOOR( DATEDIFF( CURDATE( ) , user_dateentree ) /365 ) AS dateEntree
FROM USER
INNER JOIN USER_POSTE_SERVICE
ON USER.user_id= USER_POSTE_SERVICE.ups_poste_id
INNER JOIN POSTE
ON USER_POSTE_SERVICE. ups_poste_id = POSTE.poste_id
INNER JOIN SERVICE
ON USER_POSTE_SERVICE.ups_id_serv = SERVICE.serv_id
WHERE user_id = 2
ORDER BY user_nom ASC
Is it possible to gather two requests in only one ?
From what I understood you want to simple merge the result of your sub-query to your main SELECT, if so you could try it this way:
SELECT poste_nom,
ups_type_contrat,
ENT_PRO_RESULT.entpro_date,
serv_nom,
serv_id_resp,
user_credit_cpf,
user_indice_salarial,
FLOOR( DATEDIFF( CURDATE( ) , user_dateentree ) /365 ) AS dateEntree
FROM USER
LEFT JOIN (SELECT entpro_date,
entpro_user_id
FROM ENT_PRO
ORDER BY entpro_id DESC
LIMIT 1) ENT_PRO_RESULT
ON USER.user_id = ENT_PRO_RESULT.entpro_user_id
INNER JOIN USER_POSTE_SERVICE
ON USER.user_id = USER_POSTE_SERVICE.ups_poste_id
INNER JOIN POSTE
ON USER_POSTE_SERVICE.ups_poste_id = POSTE.poste_id
INNER JOIN SERVICE
ON USER_POSTE_SERVICE.ups_id_serv = SERVICE.serv_id
WHERE user_id = 2
ORDER BY user_nom ASC
I've joined it on:
ON USER.user_id = ENT_PRO_RESULT.entpro_user_id
So you only need to specify the:
WHERE user_id = 2
And the sub-query will use the current row user id for the LEFT JOIN.
Actually i am trying to create a conversation interface like FB(Messages) and for that a sql query is used to fetch all the persons whom with user is talked already.
I need the id of the user from whom he had talked in descending order,
Like if A has chatted with B and C. Then B AND C will be result of that query and B will come first because A chatted with B recently.
My 'messages' table structure is :
http://www.softnuke.com/me/files/DB.png
This is the FB example:
http://www.softnuke.com/me/files/msg.png
This is my incorrect query which needs to be fixed:
SELECT DISTINCT(`mates`)FROM(
SELECT `time` AS `time`,`from_id` AS `mates`
FROM `messages` AS T WHERE (`from_id`=$uid OR `to_id`=$uid)
UNION
SELECT `time` AS `time`,`to_id` AS `mates`
FROM `messages` AS T WHERE (`from_id`=$uid OR `to_id`=$uid)
) AS T
WHERE `mates`!='$uid'
ORDER BY `time`
$uid will give me the variable of the user I want to fetch List(Here its A).
You seem to be getting the main person and the person they were talking to, irrespective of which one is the main person. Also not quite sure how MySQL will work out the time to order things by when you are using DISTINCT which will remove some of the records with their times.
You could get the max time and order by that:-
SELECT `mates`, MAX(`time`) AS LatestConv
FROM(
SELECT `time` AS `time`,`from_id` AS `mates`
FROM `messages` AS T WHERE `to_id`=$uid
UNION
SELECT `time` AS `time`,`to_id` AS `mates`
FROM `messages` AS T WHERE `from_id`=$uid
) AS T
GROUP BY `mates`
ORDER BY LatestConv
To get the status of that latest message:-
SELECT a.mates, a.LatestConv, IFNULL(b.Status, c.Status)
FROM
(
SELECT mates, MAX(`time`) AS LatestConv
FROM(
SELECT `time` AS `time`, from_id AS mates
FROM messages AS T
WHERE to_id = $uid
UNION
SELECT `time` AS `time`, to_id AS mates
FROM messages AS T
WHERE from_id = $uid
) AS T
GROUP BY `mates`
) a
LEFT OUTER JOIN messages b
ON a.mates = b.from_id AND a.LatestConv = b.`time` AND b.to_id = $uid
LEFT OUTER JOIN messages c
ON a.mates = c.to_id AND a.LatestConv = c.`time` AND c.from_id = $uid
ORDER BY LatestConv
Note that this might get a touch confused if there are multiple messages to the same person which all share the same latest time. If this is likely it could be coped with as follows:-
SELECT a.mates, a.LatestConv, MAX(IFNULL(b.Status, c.Status))
FROM
(
SELECT mates, MAX(`time`) AS LatestConv
FROM(
SELECT `time` AS `time`, from_id AS mates
FROM messages AS T
WHERE to_id = $uid
UNION
SELECT `time` AS `time`, to_id AS mates
FROM messages AS T
WHERE from_id = $uid
) AS T
GROUP BY `mates`
) a
LEFT OUTER JOIN messages b
ON a.mates = b.from_id AND a.LatestConv = b.`time` AND b.to_id = $uid
LEFT OUTER JOIN messages c
ON a.mates = c.to_id AND a.LatestConv = c.`time` AND c.from_id = $uid
GROUP BY a.mates, a.LatestConv
ORDER BY LatestConv
I'm looking for faster way to run this kind of statment:
SELECT *
FROM `aukcje_przedmioty`
WHERE (
(
opis NOT
IN (
SELECT opis
FROM aukcje_przedmioty
WHERE ( aktywne =1 AND user_id =6 )
)
)
AND aktywne =0
AND user_id =6
)
table aukcje_przedmioty
you can try something like
SELECT a.*
FROM `aukcje_przedmioty` a
JOIN
(
SELECT opis,user_id
FROM aukcje_przedmioty
GROUP BY opis,user_id
HAVING max(aktywne) = 0
) x
ON
x.user_id = a.user_id and
x.opis = a.opis
WHERE user_id = 6
http://sqlfiddle.com/#!2/16774/6
Use explain on your setup to see what would work best for you.
I'm a nubie in mysql queries, and I would like to ask, whether if there's someone who can help me to solve my problem. I have this complex(for me) sql. and I want to change it into a view.
SELECT
username,
user_id,
sum(result_points) AS count_points,
count(result_points) AS activity_done,
(
(
SELECT count(*) FROM `activity` WHERE periode_id = ''
) +
(
SELECT
IFNULL(sum(acs.result_points), 0)
FROM
user_activity ua
WHERE
periode_id = ''
AND ua.user_id = user_activity.user_id
AND ua.result_points IS NOT NULL
)
) AS total
FROM
user_activity
LEFT JOIN users ON users.id = user_activity.user_id
WHERE
periode_id = ''
and user_id > 0
GROUP BY user_id
ORDER BY total DESC
is there a way, to take out the "where" statement,so that i still can change it to view?
If you query is correct, create view like
Create View data as
SELECT
username,
user_id,
sum(result_points) AS count_points,
count(result_points) AS activity_done,
(
(
SELECT count(*) FROM `activity` WHERE periode_id = ''
) +
(
SELECT
IFNULL(sum(acs.result_points), 0)
FROM
user_activity ua
WHERE
periode_id = ''
AND ua.user_id = user_activity.user_id
AND ua.result_points IS NOT NULL
)
) AS total
FROM
user_activity
LEFT JOIN users ON users.id = user_activity.user_id
WHERE
periode_id = ''
and user_id > 0
GROUP BY user_id
ORDER BY total DESC
Remove where clause from view and add where clause in view, like
select * from data where user_id > 0
I have query like this:
SELECT `all_messages`.`user_1`, `messages`.*, `users`.`username`
FROM `all_messages`
JOIN `messages` ON (`all_messages`.`user_2` = `messages`.`from_user`)
JOIN `users` ON (`all_messages`.`user_2` = `users`.`id`)
WHERE `all_messages`.`user_1` = '12'
ORDER BY `messages`.`sent` DESC LIMIT 2
Now this query does what I need but my problem is with this line
ON (`all_messages`.`user_2` = `messages`.`from_user`)
It selects all data from messages where the matches was found but I need only one newest record. I hope you guys get what I mean.
If you need one "newest record" you should have a date column or something, lets name it "CREATION_TIME", so you could do something like this
SELECT AM.user_1, M.*, U.username
FROM all_messages AM, messages M , users U
WHERE AM.user_1 = '12'
AND AM.user_2 = M.from_user
AND AM.user_2 = U.id
AND M.CREATION_TIME =
(
SELECT MAX(CREATION_TIME)
FROM messages
WHERE from_user= M.from_user
)
ORDER BY M.sent DESC LIMIT 2
Edit
SELECT AM.user_1, M.*, U.username
FROM all_messages AM, messages M, users U
WHERE AM.user_1 = '12'
AND AM.user_2 = M.from_user
AND AM.user_2 = U.id
AND M.sent =
(
SELECT MAX(sent)
FROM messages
WHERE from_user= M.from_user
)
ORDER BY M.sent DESC LIMIT 2
It should work