I try to change database from 'MySQL' to 'PostgreSQL' but i have problem some of my query
SELECT
SUM( CASE WHEN b.DISPLAYNAME IS NULL THEN 0 ELSE 1 END ) AS NUMMENUDETAIL,
A.DISPLAYNAME AS GROUPNAME,
b.displayname,
D.NAME,
min( A.ROLEID ) AS ROLEID
FROM
usermenu A
LEFT JOIN usermenu B ON A.ID = B.GROUPID,
userrole C,
position D,
positiondetail E
WHERE
( A.GROUPID IS NULL )
AND D.id = E.position_id
AND A.ROLEID = E.userrole_id
AND A.ROLEID = C.ID
AND B.ROLEID = E.userrole_id
AND B.ROLEID = C.ID
AND b.displayname = 'Transaction Listing Report'
GROUP BY
A.DISPLAYNAME,
b.displayname
LIMIT 10
i use this query into "MySQL" it pass
but when i use in "PostgreSQL" it error, They want my to GROUP BY d.name
then if i GROUP BY it may have different result
How can i fix this ?
This query does not comply with the SQL standard, so it is unsurprising that it does not work on all databases. The standard requires that all columns in the SELECT list that do not appear only inside aggregate functions must be in the GROUP BY clause.
You can have the same effect by using the (again, non-standard) DISTINCT ON clause in PostgreSQL.
Related
I have a query which gives result as below, how to replace duplicate values with NULL
Query:
SELECT
word.lemma,
synset.definition,
synset.pos,
sampletable.sample
FROM
word
LEFT JOIN
sense ON word.wordid = sense.wordid
LEFT JOIN
synset ON sense.synsetid = synset.synsetid
LEFT JOIN
sampletable ON synset.synsetid = sampletable.synsetid
WHERE
word.lemma = 'good'
Result:
Required Result: all the greyed out results as NULL
First, this is the type of transformation that is generally better done at the application level. The reason is that it presupposes that the result set is in a particular order -- and you seem to be assuming this even with no order by clause.
Second, it is often simpler in the application.
However, in MySQL 8+, it is not that hard. You can do:
SELECT w.lemma,
(CASE WHEN ROW_NUMBER() OVER (PARTITION BY w.lemma, ss.definition ORDER BY st.sample) = 1
THEN ss.definition
END) as definition,
ss.pos,
st.sample
FROM word w LEFT JOIN
sense s
ON w.wordid = s.wordid LEFT JOIN
synset ss
ON s.synsetid = ss.synsetid LEFT JOIN
sampletable st
ON ss.synsetid = st.synsetid
WHERE w.lemma = 'good'
ORDER BY w.lemma, ss.definition, st.sample;
For this to work reliably, the outer ORDER BY clause needs to be compatible with the ORDER BY for the window function.
If you are using Mysql 8 try with Rank().. As I didn't have your table or data couldn't test this query.
SELECT
word.lemma
,case when r = 1 synset.definition else null end as definition
,synset.pos
,sampletable.sample
FROM
(
SELECT
word.lemma
,synset.definition
,synset.pos
,sampletable.sample
,RANK() OVER (PARTITION BY synset.definition ORDER BY synset.definition) r
FROM
(
SELECT
word.lemma,
synset.definition,
synset.pos,
sampletable.sample
FROM
word
LEFT JOIN
sense ON word.wordid = sense.wordid
LEFT JOIN
synset ON sense.synsetid = synset.synsetid
LEFT JOIN
sampletable ON synset.synsetid = sampletable.synsetid
WHERE
word.lemma = 'good'
) t
)t1;
I'm really struggling to find an answer to this issue. I want to write an if or case statement that changes a value in another column. If column 'check' is 0 then column 'points' should be 0 as well.
SELECT club_name, COALESCE(club_winner,0) AS 'check', COUNT(*) AS points,
CASE
WHEN check = '0'
THEN points = '0'
ELSE check
END as Saleable
FROM clubs c
LEFT JOIN club_results cr ON c.club_id = cr.club_winner
GROUP BY club_name ORDER BY points DESC
You can't "SET" columns in a case statement, you can return the value. Think of the case statement as a variable column. Return '0' AS Saleable (Or whatever column you wish to name).
SELECT club_name, COALESCE(club_winner,0) AS 'check', COUNT(*) AS points,
CASE
WHEN COALESCE(club_winner,0) = 0
THEN 0
ELSE COUNT(*)
END AS points_or_0_if_check_is_0
FROM clubs c
LEFT JOIN club_results cr ON c.club_id = cr.club_winner
GROUP BY club_name ORDER BY points_or_0_if_check_is_0 DESC
You can select to count only lines matching your left join like so:
SELECT
club_name,
COUNT(
CASE WHEN
club_winner IS NOT NULL
THEN
CR.id
ELSE
NULL
END
) AS `points`
FROM
clubs C
LEFT JOIN
club_results CR ON C.club_id = CR.club_winner
GROUP BY
C.club_id
ORDER BY
points DESC
select
c.investor_id as investorid,
i.name as investor_name,
inv_typ.name as type_of_investor,
(select count(*) from investor_users where user_id=iu.user_id) as num_of_investors,
(select count(*) from task_logs where campaign_id=c.id) as num_of_task_logs,
c.updated_at as updated_date,
c.call_date as calldate,
a.name as admin_name,
c.id as campaign_id
from
admins a,
investors i,
investor_types inv_typ,
campaigns c,
task_logs tl,
campaign_statuses cs,
investor_users iu
where
c.investor_id=i.id
and i.investor_type_id=inv_typ.id
and i.id=iu.investor_id
and c.campaign_status_id = cs.id
and c.assigned_to_admin_id = a.id
and c.campaign_type_id = 1
and c.campaign_status_id = (select id from campaign_statuses having id=c.campaign_status_id and cs.code ='CLOSED') and c.assigned_to_admin_id = 46
and tl.campaign_id = c.id and max((select task_logs.task_status_id from task_logs having task_logs.campaign_id = c.id)) = 9
order by c.call_date ASC
You have a max() in the where clause:
max((select task_logs.task_status_id
from task_logs
having task_logs.campaign_id = c.id)) = 9
That is an improper use of an aggregation function. Instead:
(select max(task_logs.task_status_id)
from task_logs
where task_logs.campaign_id = c.id) = 9
This glaring error was easy to spot, because it is so audacious. However, your query would benefit from the following:
Never use commas in the FROM clause. Always use proper explicit JOIN syntax. That is the proper way to express joins for two decades, so it is time for everyone to use it.
Use table aliases so queries are easier to write and to read.
Don't confuse the having clause with the where clause. That subquery should have used where.
In relation to the answer I accepted for this post, SQL Group By and Limit issue, I need to figure out how to create that query using SQLAlchemy. For reference, the query I need to run is:
SELECT t.id, t.creation_time, c.id, c.creation_time
FROM (SELECT id, creation_time
FROM thread
ORDER BY creation_time DESC
LIMIT 5
) t
LEFT OUTER JOIN comment c ON c.thread_id = t.id
WHERE 3 >= (SELECT COUNT(1)
FROM comment c2
WHERE c.thread_id = c2.thread_id
AND c.creation_time <= c2.creation_time
)
I have the first half of the query, but I am struggling with the syntax for the WHERE clause and how to combine it with the JOIN. Any one have any suggestions?
Thanks!
EDIT: First attempt seems to mess up around the .filter() call:
c = aliased(Comment)
c2 = aliased(Comment)
subq = db.session.query(Thread.id).filter_by(topic_id=122098).order_by(Thread.creation_time.desc()).limit(2).offset(2).subquery('t')
subq2 = db.session.query(func.count(1).label("count")).filter(c.id==c2.id).subquery('z')
q = db.session.query(subq.c.id, c.id).outerjoin(c, c.thread_id==subq.c.id).filter(3 >= subq2.c.count)
this generates the following SQL:
SELECT t.id AS t_id, comment_1.id AS comment_1_id
FROM (SELECT count(1) AS count
FROM comment AS comment_1, comment AS comment_2
WHERE comment_1.id = comment_2.id) AS z, (SELECT thread.id AS id
FROM thread
WHERE thread.topic_id = :topic_id ORDER BY thread.creation_time DESC
LIMIT 2 OFFSET 2) AS t LEFT OUTER JOIN comment AS comment_1 ON comment_1.thread_id = t.id
WHERE z.count <= 3
Notice the sub-query ordering is incorrect, and subq2 somehow is selecting from comment twice. Manually fixing that gives the right results, I am just unsure of how to get SQLAlchemy to get it right.
Try this:
c = db.aliased(Comment, name='c')
c2 = db.aliased(Comment, name='c2')
sq = (db.session
.query(Thread.id, Thread.creation_time)
.order_by(Thread.creation_time.desc())
.limit(5)
).subquery(name='t')
sq2 = (
db.session.query(db.func.count(1))
.select_from(c2)
.filter(c.thread_id == c2.thread_id)
.filter(c.creation_time <= c2.creation_time)
.correlate(c)
.as_scalar()
)
q = (db.session
.query(
sq.c.id, sq.c.creation_time,
c.id, c.creation_time,
)
.outerjoin(c, c.thread_id == sq.c.id)
.filter(3 >= sq2)
)
I have this QUERY:
select
a.*
from
mt_proyecto a,
mt_mockup b,
mt_diseno c,
mt_modulo d
where
a.estado = 'A' and
(
(b.encargado = '1' and b.idproyecto = a.idmtproyecto) or
(c.encargado = '1' and c.idproyecto = a.idmtproyecto) or
(d.encargado = '1' and d.idproyecto = a.idmtproyecto)
)
group by
a.idmtproyecto
order by a.finalizado asc, a.feccrea desc
Result:
Then, I run the same code on server with the same database:
Is there any problem with the query?
It seems that the query is running correctly on your server, and returning no rows. Please make sure you have the same table contents on your local machine and your server.
Other things:
Pro tip: never use SELECT * or SELECT table.* in software. Always enumerate the columns you want in your result set.
Unless you use GROUP BY with aggregate functions like SUM() or `COUNT(), and naming the correct columns from the result set, it returns unpredictable results. Read this. http://dev.mysql.com/doc/refman/5.1/en/group-by-extensions.html
I solved with this QUERY:
select
a.*
from
(
mt_proyecto a
left join mt_mockup b on
b.idproyecto = a.idmtproyecto
left join mt_diseno c on
c.idproyecto = a.idmtproyecto
left join mt_modulo d on
d.idproyecto = a.idmtproyecto
left join mt_integracion e on
e.idproyecto = a.idmtproyecto
left join mt_pruebas_internas f on
f.idproyecto = a.idmtproyecto
)
where
a.estado = 'A' and
(
(a.idmtproyecto = b.idproyecto and
b.encargado = '1' ) or
(a.idmtproyecto = c.idproyecto and
c.encargado = '1' ) or
(a.idmtproyecto = d.idproyecto and
d.encargado = '1' ) or
(a.idmtproyecto = e.idproyecto and
e.encargado = '1' ) or
(a.idmtproyecto = f.idproyecto =
f.encargado = '1' )
)
group by a.idmtproyecto
order by
a.finalizado asc, a.feccrea desc
Thanks everyone for answer me. I'll do your suggestions .