i have 3 tables
Posts_comments
comment_id, comment_post_id, comment_value, comment_time comment_user_id
1 1 test DATETIME 1
2 1 test2 DATETIME 2
3 2 test3 DATETIME 2
4 1 test4 DATETIME 2
5 1 test5 DATETIME 1
6 1 test6 DATETIME 2
Members
member_id member_fistname member_lastname member_slug
1 John Doe john-doe
2 Test User test-user
Members_photos
member_user_id member_photo_type member_photo_name
1 2 test.jpg
2 2 test2.jpg
And i have sql
SELECT
posts_comments.comment_id,
posts_comments.comment_post_id,
posts_comments.comment_value,
posts_comments.comment_time,
members.member_id,
members.member_lastname,
members.member_fistname,
members_photos.member_photo_name
FROM
posts_comments
LEFT JOIN
members ON posts_comments.comment_user_id = members.member_id
LEFT JOIN
members_photos ON members.member_id = members_photos.member_user_id
AND
members_photos.member_photo_type = 2
ORDER BY
posts_comments.comment_time DESC
LIMIT 4
But this query show only last 4 comments independently from the comment_post_id.
In this case i want to show last 4 comments for every comment_post_id (in this example: 4 comments where comment_post_id = 1 and 1 comment where comment_post_id = 2).
I hope I wrote it clearly enough.
Thx 4 help :)
use row_number() window function if it mariadb version MariaDB 10.2.0 or greatere
select a.* from ( SELECT
posts_comments.comment_id,
posts_comments.comment_post_id,
posts_comments.comment_value,
posts_comments.comment_time,
members.member_id,
members.member_lastname,
members.member_fistname,
members_photos.member_photo_name,
row_number()over(partition by posts_comments.comment_post_id order by posts_comments.comment_time desc) rn
FROM
posts_comments
LEFT JOIN
members ON posts_comments.comment_user_id = members.member_id
LEFT JOIN
members_photos ON members.member_id = members_photos.member_user_id
AND
members_photos.member_photo_type = 2
) a where a.rn<=4
Related
I seek to find the maximum timestamp (ob.create_ts) for each group of marketid's (ob.marketid), joining tables obe (ob.orderbookid = obe.orderbookid) and market (ob.marketid = m.marketid). Although there are a number of solutions posted like this for a single table, when I join multiple tables, I get redundant results. Sample table and desired results below:
table: ob
orderbookid
marketid
create_ts
1
1
1664635255298
2
1
1664635255299
3
1
1664635255300
4
2
1664635255301
5
2
1664635255302
6
2
1664635255303
table: obe
orderbookentryid
orderbookid
entryname
1
1
'entry-1'
2
1
'entry-2'
3
1
'entry-3'
4
2
'entry-4'
5
2
'entry-5'
6
3
'entry-6'
7
3
'entry-7'
8
4
'entry-8'
9
5
'entry-9'
10
6
'entry-10'
table: m
marketid
marketname
1
'market-1'
2
'market-2'
desired results
ob.orderbookid
ob.marketid
obe.orderbookentryid
obe.entryname
m.marketname
3
1
6
'entry-6'
'market-1'
3
1
7
'entry-7'
'market-1'
6
2
10
'entry-10'
'market-2'
Use ROW_NUMBER() to get a properly filtered ob table. Then JOIN the other tables onto that!
WITH
ob_filtered AS (
SELECT
orderbookid,
marketid
FROM
(
SELECT
*,
ROW_NUMBER() OVER (
PARTITION BY
marketid
ORDER BY
create_ts DESC
) AS create_ts_rownumber
FROM
ob
) ob_with_rownumber
WHERE
create_ts_rownumber = 1
)
SELECT
ob_filtered.orderbookid,
ob_filtered.marketid,
obe.orderbookentryid,
obe.entryname,
m.marketname
FROM
ob_filtered
JOIN m
ON m.marketid = ob_filtered.marketid
JOIN obe
ON ob_filtered.orderbookid = obe.orderbookid
;
Below is a very oversimplified problem I am trying to solve
I have the following tables:
**quiz**
id title
--------------
1 first
2 second
3 third
4 fourth
5 fifth
**quiz_status**
id status user_id quiz_id
-------------------------------
1 0 1 1
2 0 1 2
3 0 1 3
if a I run the following:
select *
from quiz as q
left join quiz_status as qs
ON q.id = qs.quiz_id
where qs.user_id=1
I'd get:
id title id status user_id quiz_id
-------------------------------------------
1 first 1 0 1 1
2 second 2 0 1 2
3 third 3 0 1 3
4 fourth null null null null
5 fifth null null null null
I would like to be able to insert values where missing/null in the quiz_status table.
so the final outcome would be:
id title id status user_id quiz_id
-------------------------------------------
1 first 1 0 1 1
2 second 2 0 1 2
3 third 3 0 1 3
4 fourth 4 0 1 4
5 fifth 5 0 1 5
What would be the insert statement for that?
Consider the insert ... select syntax:
insert into quiz_status(status, user_id, quiz_id)
select 0, u.user_id, q.id
from (select distinct user_id from quiz_status) u
cross join quiz q
left join quiz_status qz on q.id = qz.quiz_id and u.user_id = qz.user_id
where qz.quiz_id is null
This works by generating all combinations of users and quizs, and then left joining the status table to filter on missing records. In the real life, you would likely have a users table that you can use in place of the select distinct subquery.
If you need just one user it's simpler:
insert into quiz_status(status, user_id, quiz_id)
select 0, 1, q.id
from quiz q
left join quiz_status qz on q.id = qz.quiz_id and qz.user_id = 1
where qz.quiz_id is null
Note: presumably, id is a serial column so I left it apart in the inserts.
I want to create a rank column using existing rank and binary columns. Suppose for example a table with ID, RISK, CONTACT, DATE. The existing rank is RISK, say 1,2,3,NULL, with 3 being the highest. The binary-valued is CONTACT with 0,1 or FAILURE/SUCESS. I want to create a new RANK that will order by RISK once a certain number of successful contacts has been exceeded.
For example, suppose the constraint is a minimum of 2 successful contacts. Then the rank should be created as follows in the two instances below:
Instance 1. Three ID, all have a min of two successful contacts. In that case the rank mirrors the risk:
ID risk contact date rank
1 3 S 1 3
1 3 S 2 3
1 3 F 3 3
1 3 F 4 3
2 2 S 1 2
2 2 S 2 2
2 2 F 3 2
2 2 F 4 2
3 1 S 1 1
3 1 S 2 1
3 1 S 3 1
Instance 2. Suppose ID=1 has only one successful contact. In that case it is relegated to the lowest rank, rank=1, while ID=2 gets the highest value, rank=3, and ID=3 maps to rank=2 because it satisfies the constraint but has a lower risk value than ID=2:
ID risk contact date rank
1 3 S 1 1
1 3 F 2 1
1 3 F 3 1
1 3 F 4 1
2 2 S 1 3
2 2 S 2 3
2 2 F 3 3
2 2 F 4 3
3 1 S 1 2
3 1 S 2 2
3 1 S 3 2
This is SQL, specifically Hive. Thanks in advance.
Edit - I think Gordon Linoff's code does it correctly. In the end, I used three interim tables. The code looks like that:
First,
--numerize risk, contact
select A.* ,
case when A.risk = 'H' then 3
when A.risk = 'M' then 2
when A.risk = 'L' then 1
when A.risk is NULL then NULL
when A.risk = 'NULL' then NULL
else -999 end as RISK_RANK,
case when A.contact = 'Successful' then 1
else NULL end as success
Second,
-- sum_successes_by_risk
select A.* ,
B.sum_successes_by_risk
from T as A
inner join
(select A.person, A.program, A.risk, sum(a.success) as sum_successes_by_risk
from T as A
group by A.person, A.program, A.risk
) as B
on A.program = B.program
and A.person = B.person
and A.risk = B.risk
Third,
--Create table that contains only max risk category
select A.* ,
B.max_risk_rank
from T as A
inner join
(select A.person, max(A.risk_rank) as max_risk_rank
from T as A
group by A.person
) as B
on A.person = B.person
and A.risk_rank = B.max_risk_rank
This is hard to follow, but I think you just want window functions:
select t.*,
(case when sum(case when contact = 'S' then 1 else 0 end) over (partition by id) >= 2
then risk
else 1
end) as new_risk
from t;
I am trying to select the last change value per group.
I have a table
MMID column is incremental
MMID GID MID Value Bundle DateEntered
1 1 1 1 2 17/8/15 05:05:04
2 1 2 2 3 16/8/15 05:05:06
3 1 3 3 2 15/8/15 05:05:07
4 1 1 0 2 18/8/15 05:05:08
5 2 2 1 1 18/8/15 05:05:05
6 2 2 2 2 18/8/15 06:06:06
7 2 4 3 1 17/8/15 06:06:06
8 2 4 3 2 18/8/15 06:06:07
Here, I want the last change 'Value' in the last 24 hour(Having Date 18th August).
From the below query, I can get that. But even if the bundle value is changed, then I get that row.
But I want only rows when 'Value' is changed, or 'Value and Bundle' are changed. But not only when Bundle is changed
Desired output
MMID GID MID Value Bundle DateEntered
4 1 1 0 2 18/8/15 05:05:08
6 2 2 2 2 18/8/15 06:06:06
The query I tried is :
select yt1.*
from Table1 yt1
left outer join Table1 yt2
on (yt1.GID = yt2.GID and yt1.MID = yt2.MID
and yt1.MMID < yt2.MMID)
where yt2.MMID is null and yt2.GID is null and yt2.MID is null and yt1.DateEntered > '2015-08-18 00:00:00' ;
The output i get from here is:
MMID GID MID Value Bundle DateEntered
4 1 1 0 2 18/8/15 05:05:08
6 2 2 2 2 18/8/15 06:06:06
8 2 4 3 2 18/8/15 06:06:07
I should not be getting the last row here.
Can anyone tell me what should I change here.
Not really following the logic of your attempt, but here is how I would get the desired results:
WITH cte AS (
SELECT *,
ROW_NUMBER() OVER (PARTITION BY GID, MID ORDER BY MMID) AS rn
FROM Table
)
, cte2 AS (
SELECT t1.* FROM cte t1
INNER JOIN cte t2
ON t1.GID=t2.GID
AND t1.MID=t2.MID
AND t1.value<>t2.value
AND t1.rn=t2.rn+1
)
SELECT *
FROM cte2
WHERE MMID=(
SELECT TOP 1 MMID
FROM cte2 c2
WHERE cte2.GID=c2.GID
AND cte2.MID=c2.MID
ORDER BY MMID DESC
)
NB: If you don't want to include the rn column in the final results, use a column list instead of SELECT *.
Ive got a table:
UserA UserB UserBB UserAA
for example:
1 2 2 1
1 3 3 1
2 1 1 2
2 4 4 2
2 5 5 2
5 2 2 5
What I want to achieve is to remove rows (duplicates) like to only leave rows as in example:
1 2 2 1
1 3 3 1
2 4 4 2
2 5 5 2
2 1 1 2 -> deleted because there is already 1 2 2 1
5 2 2 5 -> deleted because there is already 2 5 5 2
How to write such a query ?
Thanks for help
-- Find Duplicate Rows
SELECT MAX(ID) as ID, CustName, Pincode FROM #Customers
GROUP BY CustName, Pincode
HAVING COUNT(*) > 1
-- Delete Duplicate Rows
DELETE FROM #Customers
WHERE ID IN
( SELECT MAX(ID) FROM #Customers
GROUP BY CustName, Pincode
HAVING COUNT(*) > 1)
Taken from MSDN. :
http://archive.msdn.microsoft.com/SQLExamples/Wiki/View.aspx?title=DuplicateRows
Let me know if you are unable to figure it out from that code.
This may be a little bit closer to your needs. :
DELETE FROM TABLE
WHERE USERA IN ( SELECT MAX(USERA) FROM TABLE
GROUP BY USERA, USERB, USERBB, USERAA HAVING COUNT(*) > 1)
The below also covers situations where UserA and UserB are equal between the two rows but UserAA and UserBB are switched and the reverse. Your question is a bit unclear about what exactly constitutes a duplicate. Hopefully this points you in the right direction at the very least though.
I would turn this into a SELECT statement first though and make sure that it is returning the rows that you think should be deleted and only those rows.
DELETE T1
FROM
My_Table T1
INNER JOIN My_Table T2 ON
(
T2.UserA = T1.UserA AND
T2.UserB = T1.UserB AND
T2.UserAA = T1.UserBB AND
T2.UserBB = T1.UserAA AND
T2.UserAA < T2.UserBB
) OR
(
T2.UserA = T1.UserB AND
T2.UserB = T1.UserA AND
T2.UserAA = T1.UserAA AND
T2.UserBB = T1.UserBB AND
T2.UserA < T2.UserB
) OR
(
T2.UserA = T1.UserB AND
T2.UserB = T1.UserA AND
T2.UserAA = T1.UserBB AND
T2.UserBB = T1.UserAA AND
T2.UserA < T2.UserB
)
It was Enough just to add:
Where UserA < UserB