I have
users
------------------------
id | name | other_stuff.....
.
engagement
------------------------
user_id | type_code |
type_code is a varchar, but either A, B, C or NULL
[ EDIT for clarity: Users can have many engagements of each type code. SO I want to count how many they have of each. ]
I want to return ALL user rows, but with a count of A, B and C type engagements. E.g.
users_result
------------------------
user_id | user_name | other_stuff..... | count_A | count_B | count_C |
I've done quite a bit of searching, but found the following issues with other solutions:
The "other_stuff..." is actually grouped / concatenated results from a dozen other joins, so it's a bit of a monster already. So I need to be able to just add the additional fields to the pre-existing "SELECT ...... FROM users..." query.
The three additional required bits of data all come from the same engagement table, each with their own condition. I havent found anything to allow me to use the three conditions on the same related table.
Thanks
[edit]
I tried to simplify the question so people didn't have to look through loads of unnecessary stuff, but seems I might not have given enough info. Here is 'most' of the original query. I've taken out a lot of the selected fields as there are loads, but I've left most of the joins in so you can see basically what is actually going on.
SELECT
user.id,
user.first_name,
user.second_name,
GROUP_CONCAT(DISTINCT illness.id ORDER BY illness.id SEPARATOR ',' ) AS reason_for_treatment,
IF(ww_id=1000003, 1,'') as user_refused_program,
Group_CONCAT(DISTINCT physical_activity.name SEPARATOR ', ') AS programme_options,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_A,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm12%' THEN 1 ELSE NULL END) as count_B,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_C
FROM `user`
LEFT JOIN session AS session_induction ON (user.id = session_induction.user_id AND session_induction.session_type_id = 3)
LEFT JOIN stats AS stats_induction ON session_induction.id = stats_induction.session_id
LEFT JOIN session AS session_interim ON (user.id = session_interim.user_id AND session_interim.session_type_id = 4)
LEFT JOIN stats AS stats_interim ON session_interim.id = stats_interim.session_id
LEFT JOIN session AS session_final ON (user.id = session_final.user_id AND session_final.session_type_id = 5)
LEFT JOIN stats AS stats_final ON session_final.id = stats_final.session_id
LEFT JOIN user_has_illness ON user.ID = user_has_illness.user_id
LEFT JOIN illness ON user_has_illness.illness_id = illness.id
LEFT JOIN user_has_physical_activity ON user.ID = user_has_physical_activity.user_id
LEFT JOIN physical_activity ON user_has_physical_activity.physical_activity_id = physical_activity.id
LEFT JOIN engagement_item ON user.ID = engagement_item.user_ID
WHERE (user.INDUCTION_DATE>='2010-06-09' AND user.INDUCTION_DATE<='2011-06-09' AND user.archive!='1' )
GROUP BY user.id, engagement_item.user_id
It's worth mentioning that it works fine - returns all users with all details required. Except for the count_A B and C cols.
[edit added slightly more simplified query below]
Stripped out the unrelated joins and selects.
SELECT
user.id,
user.first_name,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_A,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm12%' THEN 1 ELSE NULL END) as count_B,
COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_C
FROM `user`
LEFT JOIN engagement_item ON user.ID = engagement_item.user_ID
GROUP BY user.id, engagement_item.user_id
SELECT e.user_id, u.name,
COUNT(CASE type_code WHEN 'A' THEN 1 ELSE NULL END) as count_A,
COUNT(CASE type_code WHEN 'B' THEN 1 ELSE NULL END) as count_B,
COUNT(CASE type_code WHEN 'C' THEN 1 ELSE NULL END) as count_C
FROM engagement e join users u on (e.user_id = u.id)
GROUP BY e.user_id, u.name
I would use COUNT instead of SUM just because that is what it is made for, counting things when not NULL.
SELECT
user.id,
user.first_name,
user.second_name,
GROUP_CONCAT(DISTINCT illness.id ORDER BY illness.id SEPARATOR ',' ) AS reason_for_treatment,
IF(ww_id=1000003, 1,'') as user_refused_program,
Group_CONCAT(DISTINCT physical_activity.name SEPARATOR ', ') AS programme_options,
ei.count_A, ei.count_B, ei.count_C
FROM `user`
LEFT JOIN ( SELECT user_id
, COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_A
, COUNT(CASE WHEN engagement_item.type_code LIKE 'wm12%' THEN 1 ELSE NULL END) as count_B
, COUNT(CASE WHEN engagement_item.type_code LIKE 'wm6%' THEN 1 ELSE NULL END) as count_C
FROM engagement_item
GROUP BY userid ) ei
LEFT JOIN session AS session_induction ON (user.id = session_induction.user_id AND session_induction.session_type_id = 3)
LEFT JOIN stats AS stats_induction ON session_induction.id = stats_induction.session_id
LEFT JOIN session AS session_interim ON (user.id = session_interim.user_id AND session_interim.session_type_id = 4)
LEFT JOIN stats AS stats_interim ON session_interim.id = stats_interim.session_id
LEFT JOIN session AS session_final ON (user.id = session_final.user_id AND session_final.session_type_id = 5)
LEFT JOIN stats AS stats_final ON session_final.id = stats_final.session_id
LEFT JOIN user_has_illness ON user.ID = user_has_illness.user_id
LEFT JOIN illness ON user_has_illness.illness_id = illness.id
LEFT JOIN user_has_physical_activity ON user.ID = user_has_physical_activity.user_id
LEFT JOIN physical_activity ON user_has_physical_activity.physical_activity_id = physical_activity.id
LEFT JOIN engagement_item ON user.ID = engagement_item.user_ID
WHERE (user.INDUCTION_DATE>='2010-06-09' AND user.INDUCTION_DATE<='2011-06-09' AND user.archive!='1' )
GROUP BY user.id, engagement_item.user_id, ei.count_A, ei.count_B, ei.count_C
Something like this perhaps?
select e.user_id, u.name,
sum(case e.type_code when 'A' then 1 else 0 end) as count_A,
sum(case e.type_code when 'B' then 1 else 0 end) as count_B,
sum(case e.type_code when 'C' then 1 else 0 end) as count_C
from engagement e join users u on (e.user_id = u.id)
group by e.user_id, u.name
The interesting part is the use of CASE inside the SUM to split the counting into three chunks.
Related
I have a user-table which contains users information with the fields user_id, fullname, age, username, password and other is tests-table with the fields id, user_id, test_type
When I write the below query
select users.user_id, fullname,
(CASE WHEN test_table.user_id=users.id and test_table.type = 'objectives' THEN 'yes' ELSE 'no' END) AS written_objectives,
(CASE WHEN test_table.user_id=users.id and test_table.type = 'theory' THEN 'yes' ELSE 'no' END) AS written_theory,
from users
LEFT JOIN test_table ON users.id = test_table.user_id
WHERE users.user_id = 1
I get the results like this
user_id|fullname| test_type | written_objectives| written_theory
1 | Ben. | objectivs | yes | no
1 | Ben. | theory | no | yes
But I want the results like this
user_id|fullname| test_type | written_objectives| written_theory
1 | Ben. | objectivs | yes | yes
From the above scenario, the user with id of 1 has submitted both objectives and theory.
You can do conditional aggregation:
select u.user_id, u.fullname,
max(tt.type = 'objectives') written_objectives,
max(tt.type = 'theory' ) written_theory
from users u
left join test_table tt on u.id = tt.user_id
where u.user_id = 1
group by u.user_id
This generates 0/1 values rather than 'yes'/'no' - which I find more expressive. But if you really want thoses strings, then:
select u.user_id, u.fullname,
case when max(tt.type = 'objectives') then 'yes' else 'no' end written_objectives,
case when max(tt.type = 'theory' ) then 'yes' else 'no' end written_theory
from users u
left join test_table tt on u.id = tt.user_id
where u.user_id = 1
group by u.user_id
Notes:
there is no need to repeat the join condition in the conditional expression - the left join handles that already
table aliases make the query easier to write and read
In below query (Mentors) are 13 which shows me 26, while (SchoolSupervisor) are 5 which shows me 10 which is wrong. it is because of the Evidence which having 2 evidance, because of 2 evidence the Mentors & SchoolSupervisor values shows me double.
please help me out.
Query:
select t.c_id,t.province,t.district,t.cohort,t.duration,t.venue,t.v_date,t.review_level, t.activity,
SUM(CASE WHEN pr.p_association = "Mentor" THEN 1 ELSE 0 END) as Mentor,
SUM(CASE WHEN pr.p_association = "School Supervisor" THEN 1 ELSE 0 END) as SchoolSupervisor,
(CASE WHEN count(file_id) > 0 THEN "Yes" ELSE "No" END) as evidence
FROM review_m t , review_attndnce ra
LEFT JOIN participant_registration AS pr ON pr.p_id = ra.p_id
LEFT JOIN review_files AS rf ON rf.training_id = ra.c_id
WHERE 1=1 AND t.c_id = ra.c_id
group by t.c_id, ra.c_id order by t.c_id desc
enter image description here
You may perform the aggregations in a separate subquery, and then join to it:
SELECT
t.c_id,
t.province,
t.district,
t.cohort,
t.duration,
t.venue,
t.v_date,
t.review_level,
t.activity,
pr.Mentor,
pr.SchoolSupervisor,
rf.evidence
FROM review_m t
INNER JOIN review_attndnce ra
ON t.c_id = ra.c_id
LEFT JOIN
(
SELECT
p_id,
COUNT(CASE WHEN p_association = 'Mentor' THEN 1 END) AS Mentor,
COUNT(CASE WHEN p_association = 'School Supervisor' THEN 1 END) AS SchoolSupervisor,
FROM participant_registration
GROUP BY p_id
) pr
ON pr.p_id = ra.p_id
LEFT JOIN
(
SELECT
training_id,
CASE WHEN COUNT(file_id) > 0 THEN 'Yes' ELSE 'No' END AS evidence
FROM review_files
GROUP BY training_id
) rf
ON rf.training_id = ra.c_id
ORDER BY
t.c_id DESC;
Note that this also fixes another problem your query had, which was that you were selecting many columns which did not appear in the GROUP BY clause. Under this refactor, there is nothing wrong with your current select, because the aggregation take place in a separate subquery.
try adding this to the WHERE part of your query
AND pr.p_id IS NOT NULL AND rf.training_id IS NOT NULL
You can add a group by pr.p_id to remove the duplicate records there. Since, the group by on pr is not present as of now, there might be multiple records of same p_id for same ra
group by t.c_id, ra.c_id, pr.p_id order by t.c_id desc
query taking 1 minute to fetch results
SELECT
`jp`.`id`,
`jp`.`title` AS game_title,
`jp`.`game_type`,
`jp`.`state_abb` AS game_state,
`jp`.`location` AS game_city,
`jp`.`zipcode` AS game_zipcode,
`jp`.`modified_on`,
`jp`.`posted_on`,
`jp`.`game_referal_amount`,
`jp`.`games_referal_amount_type`,
`jp`.`status`,
`jp`.`is_flaged`,
`u`.`id` AS employer_id,
`u`.`email` AS employer_email,
`u`.`name` AS employer_name,
`jf`.`name` AS game_function,
`jp`.`game_freeze_status`,
`jp`.`game_statistics`,
`jp`.`ats_value`,
`jp`.`integration_id`,
`u`.`account_manager_id`,
`jp`.`model_game`,
`jp`.`group_id`,
(CASE
WHEN jp.group_id != '0' THEN gm.group_name
ELSE 'NA'
END) AS group_name,
`jp`.`priority_game`,
(CASE
WHEN jp.country != 'US' THEN jp.country_name
ELSE ''
END) AS game_country,
IFNULL((CASE
WHEN
`jp`.`account_manager_id` IS NULL
OR `jp`.`account_manager_id` = 0
THEN
(SELECT
(CASE
WHEN
account_manager_id IS NULL
OR account_manager_id = 0
THEN
`u`.`account_manager_id`
ELSE account_manager_id
END) AS account_manager_id
FROM
user_user
WHERE
id = (SELECT
user_id
FROM
game_user_assigned
WHERE
game_id = `jp`.`id`
LIMIT 1))
ELSE `jp`.`account_manager_id`
END),
`u`.`account_manager_id`) AS acc,
(SELECT
COUNT(recach_limit_id)
FROM
recach_limit
WHERE
recach_limit = '1'
AND recach_limit_game_id = rpr.recach_limit_game_id) AS somewhatgame,
(SELECT
COUNT(recach_limit_id)
FROM
recach_limit
WHERE
recach_limit = '2'
AND recach_limit_game_id = rpr.recach_limit_game_id) AS verygamecommitted,
(SELECT
COUNT(recach_limit_id)
FROM
recach_limit
WHERE
recach_limit = '3'
AND recach_limit_game_id = rpr.recach_limit_game_id) AS notgame,
(SELECT
COUNT(joa.id) AS applicationcount
FROM
game_refer_to_member jrmm
INNER JOIN
game_refer jrr ON jrr.id = jrmm.rid
INNER JOIN
game_applied joa ON jrmm.id = joa.referred_by
WHERE
jrmm.STATUS = '1'
AND jrr.referby_user_id IN (SELECT
ab_testing_user_id
FROM
ab_testing)
AND joa.game_post_id = rpr.recach_limit_game_id
AND (rpr.recach_limit = 1
OR rpr.recach_limit = 2)) AS gamecount
FROM
(`game_post` AS jp)
JOIN
`user_info` AS u ON `jp`.`user_user_id` = `u`.`id`
JOIN
`game_functional` jf ON `jp`.`game_functional_id` = `jf`.`id`
LEFT JOIN
`group_musesm` gm ON `gm`.`group_id` = `jp`.`group_id`
LEFT JOIN
`recach_limit` rpr ON `jp`.`id` = `rpr`.`recach_limit_game_id`
WHERE
`jp`.`status` != '3'
GROUP BY `jp`.`id`
ORDER BY `posted_on` DESC
LIMIT 10
I would first suggest not nesting select statements because this will cause an n^x performance hit on every xth level and I see at least 3 levels of selects inside this query.
Add index
INDEX(status, posted_on)
Move LIMIT inside
Then, instead of saying
FROM (`game_post` AS jp)
say
FROM ( SELECT id FROM game_post
WHERE status != 3
ORDER BY posted_on DESC
LIMIT 10 ) AS ids
JOIN game_post AS jp USING(id)
(I am assuming that the PK of jp is (id)?)
That should efficiently use the new index to get the 10 ids needed. Then it will reach back into game_post to get the other columns.
LEFT
Also, don't say LEFT unless you need it. It costs something to generate NULLs that you may not be needing.
Is GROUP BY necessary?
If you remove the GROUP BY, does it show dup ids? The above changes may have eliminated the need.
IN(SELECT) may optimize poorly
Change
AND jrr.referby_user_id IN ( SELECT ab_testing_user_id
FROM ab_testing )
to
AND EXISTS ( SELECT * FROM ab_testing
WHERE ab_testing_user_id = jrr.referby_user_id )
(This change may or may not help, depending on the version you are running.)
More
Please provide EXPLAIN SELECT if you need further assistance.
I have a query that looks like this:
SELECT
app.application_id,
j.job_number,
j.job_id,
j.job_title,
j.job_city,
j.job_state,
p.person_id AS candidate_id,
p.first_name,
p.last_name,
app.start_date,
ope1.percent_complete,
MAX(CASE
WHEN r.role_display_name = 'ENG - Recruiter' THEN
(SELECT CASE WHEN COUNT(last_name) = 0 THEN
'Unassigned'
ELSE
COUNT(last_name)
END AS uname
FROM users
JOIN job_roles ON job_roles.user_id = users.user_id
WHERE job_id = j.job_id
AND role_id = r.role_id
)
ELSE '' END) AS role_3
My problem is that COUNT(last_name) will not return 0, because there are no records returned, so there is no value of NULL. All makes sense, however I have tried wrapping it in IFNULL(), ISNULL() and none of them seem to fix this problem. How can I get it to return 0 when there are no records? Do I need another subquery inside the COUNT() aggregate? I would really like to not use another subquery....
If understand correctly what you want you can try to rewrite it this way
SELECT ...
,MAX(CASE WHEN r.role_display_name = 'ENG - Recruiter'
THEN COALESCE(NULLIF(
(
SELECT COUNT(last_name)
FROM users JOIN job_roles
ON job_roles.user_id = users.user_id
WHERE job_id = j.job_id
AND role_id = r.role_id
), 0), 'Unassigned')
ELSE ''
END) as role_3
...
This is my query:
SELECT usr.id,
count(DISTINCT sol.id) as 'Asked',
count(DISTINCT ans.id) as 'Answered',
sum(DISTINCT CASE ans.accepted WHEN 1 THEN 1 ELSE 0 end) as 'Accepted'
FROM tbl_users usr
LEFT JOIN tbl_solutions sol on sol.authorID = usr.id
LEFT JOIN tbl_solution_answers ans on ans.authorID = usr.id
group by usr.id, sol.authorID
My above query with the sum(DISTINCT CASE ans.accepted WHEN 1 THEN 1 ELSE 0 end) only ever returns 1 though I know that's not the case. I've tried adding a group clause on the ans.authorID but it has no effect.
How can I get the sum of all rows from the tbl_solution_answers ans table where the authorID is that of tbl_users.id and Accepted is 1.
SELECT usr.id,
count(DISTINCT sol.id) as 'Asked',
count(DISTINCT ans.id) as 'Answered',
count(DISTINCT case ans.accepted when 1 then ans.id end) as 'Accepted'
FROM tbl_users usr
LEFT JOIN tbl_solutions sol on sol.authorID = usr.id
LEFT JOIN tbl_solution_answers ans on ans.authorID = usr.id
group by usr.id, sol.authorID, ans.authorID
After so many permutations count(DISTINCT case ans.accepted when 1 then ans.id end) as 'Accepted' seems to work. Now if an authorID in tbl_solution_answers has 8 rows they'll all be returned as Answered and if say 3 of them are Accepted then 3 is returned as Accepted.