Can anyone help me with the sequel syntax for the following the ruby orm sequel:
SELECT *, (SELECT COUNT(*) FROM todos WHERE reference_email_id = "emails".id) todo_count
FROM "emails"
INNER JOIN "email_participants"
ON ("email_participants"."email_id" = "emails"."id")
WHERE ("user_id" = 1)
I cannot quite get the syntax, I have this so far:
scope = Email.inner_join(:email_participants, {email_id: :id})
.where(user_id: query.user_id)
.select_append {
Attachment.where(reference_email_id: Sequel.qualify(:emails, :id))
.count(:id)
.exists
.as(:attachment_count)
}
I get the following error:
missing FROM-clause entry for table "emails" LINE 1: ... FROM
"attachments" WHERE ("reference_email_id" = "emails"."...
My guess is you should remove the .exists line. It's hard to say conclusively since you didn't post the SQL produced.
Related
Need a help regarding QueryDsl using BooleanExpression. Find the requirement below.
I have Enquiry and Followup table. OneToMany mapping in between them. 1 Enquiry having many followup.
Suppose i have 5 enquiries. for each enquiry i have 3 followup.
Expectation is ..i need last record of followup for each enquiry.
Please find the different ways i have tried.
QBuyerFollowUp qBuyerfollowup = QBuyerFollowUp.buyerFollowUp;
ListPath<BuyerFollowUp, QBuyerFollowUp> followUpList = qBuyerEnquiry.followUpList;
BooleanExpression expression = commonExpression.and(new JPAQuery<>().select(qBuyerfollowup.nextDate).from(qBuyerfollowup)
.where(qBuyerfollowup.eq(followUpList.any()))
.orderBy(qBuyerfollowup.followUpId.desc()).limit(1).eq(new Date());
please ignore commonExpression which is an another expression.
Error: Subquery returns more than 1 row
BooleanExpression expression = followUpList.any().followUpId.in(new JPAQuery<QBuyerFollowUp>().select(qBuyerfollowup.followUpId.max())
.from(qBuyerfollowup).groupBy(qBuyerfollowup.buyerEnquiry.id)
.having(qBuyerfollowup.nextDate.eq(dateFormat.parse(dateFormat.format(new Date())))));
Error: unknown column nextDate.
Here generated query is:
select count(buyerenqui0_.id) as col_0_0_ from buyer_enquiry buyerenqui0_ where
buyerenqui0_.assigned_to= 79 and
(buyerenqui0_.created_at between "2020-05-01 00:00:00" and "2020-05-31 23:59:59") and buyerenqui0_.enq_status<> "Dropped" and
not ( not (exists (select followupli1_.id from buyer_followup followupli1_ where buyerenqui0_.id=followupli1_.buyer_enquiry_id)))
and (exists (select 1 from buyer_followup followupli2_ where buyerenqui0_.id=followupli2_.buyer_enquiry_id and
(followupli2_.id in (select max(a.id) from buyer_followup a group by a.buyer_enquiry_id having date(a.next_date)=date(now())))));
solution: If will remove alias name 'a' from this query
select max(a.id) from buyer_followup a group by a.buyer_enquiry_id having date(a.next_date)=date(now())))
it is working fine.
But we don't have any control on this because alias name is generated by Spring.
You can't join subqueries in JPQL, but you can project them, which should be sufficient in this case:
QInquiry inquiry = QInquiry.inquiry;
QFollowup followup = QFollowup.followup;
Map<Inquiry, Followup> results = query().from(inquiry)
.transform(GroupBy.groupBy(inquiry).as(query().from(followup)
.where(followup.inquiry.eq(inquiry)
.orderBy(followup.id.desc())
.limit(1)))
I have a table which contains ~600k records and 33 columns. In my project I am using EF Core (2.0.1) to retrieve data from database. I am having issues with below code:
var theCounter = (from f in _context.tblData.Take(100000)
group f by f.TypeId into data
select new DataDto { ID = data.Key, Count = data.Count() }).ToList();
This code is a part of REST API and when I am testing it from SOAP UI, I am gettin timeout error. When I tested the code for
Take(1000)
There are around 300 unique TypeIds.
it works fine. Any ideas how I can make it work?
-- EDIT 1:
Here is what I see when debugging the code:
Microsoft.EntityFrameworkCore.Query:Warning: Query: '(from TblData <generated>_1 in DbSet<TblData> select [<generated>_1]).Take(__p_0)' uses a row limiting operation (Skip/Take) without OrderBy which may lead to unpredictable results.
Microsoft.EntityFrameworkCore.Query:Warning: Query: '(from TblData <generated>_1 in DbSet<TblData> select [<generated>_1]).Take(__p_0)' uses a row limiting operation (Skip/Take) without OrderBy which may lead to unpredictable results.
Microsoft.EntityFrameworkCore.Query:Warning: The LINQ expression 'GroupBy([f].TypeId, [f])' could not be translated and will be evaluated locally.
Microsoft.EntityFrameworkCore.Query:Warning: The LINQ expression 'GroupBy([f].TypeId, [f])' could not be translated and will be evaluated locally.
Microsoft.EntityFrameworkCore.Query:Warning: The LINQ expression 'Count()' could not be translated and will be evaluated locally.
Microsoft.EntityFrameworkCore.Database.Command:Information: Executed DbCommand (131ms) [Parameters=[#__p_0='?'], CommandType='Text', CommandTimeout='30']
SELECT [t2].[Id], [t2].[at], [t2].[add], [t2].[AddDate], [t2].[aftc], [t2].[aftcd], [t2].[aid], [t2].[afl], [t2].[prdid], [t2].[cid], [t2].[TypeId], [t2].[env], [t2].[ext], [t2].[extddcode], [t2].[fn], [t2].[fn], [t2].[fic], [t2].[gid], [t2].[grp], [t2].[hnm], [t2].[IP], [t2].[icid], [t2].[ln], [t2].[lg], [t2].[pcid], [t2].[ret], [t2].[rts], [t2].[rnam], [t2].[sled], [t2].[seq], [t2].[sid], [t2].[styp]
FROM (
SELECT TOP(#__p_0) [t1].[Id], [t1].[at], [t1].[add], [t1].[AddDate], [t1].[aftc], [t1].[aftcd], [t1].[aid], [t1].[afl], [t1].[prdid], [t1].[cid], [t1].[TypeId], [t1].[env], [t1].[ext], [t1].[extddcode], [t1].[fn], [t1].[fn], [t1].[fic], [t1].[gid], [t1].[grp], [t1].[hnm], [t1].[IP], [t1].[icid], [t1].[ln], [t1].[lg], [t1].[pcid], [t1].[ret], [t1].[rts], [t1].[rnam], [t1].[sled], [t1].[seq], [t1].[sid], [t1].[styp]
FROM [TblData] AS [t1]
) AS [t2]
WHERE [t2].[TypeId] IS NOT NULL
ORDER BY [t2].[TypeId]
I think it is not translated properly. Any ideas why?
-- EDIT 2:
I have changed my queries to:
var query = _context.TblData
.Select(a => new {ID = a.Id, TypeId= a.TypeId})
.Distinct();
var q1 = query.GroupBy(p => p.TypeId)
.Select(g => new DataDto {TypeId= g.Key, Count = g.Count()});
return await q1.ToListAsync();
But it was translated to:
SELECT DISTINCT [a0].[Id], [a0].[TypeId] AS [TypeId]
FROM [tblData] AS [a0]
ORDER BY [a0].[TypeId]
When I checked directly in the database this query takes 14 seconds to execute. Any idea why it was not translated to something like:
SELECT DISTINCT [a0].[Id], COUNT([TypeId]) AS [TypeId]
FROM [tblData] AS [a0]
GROUP BY COUNT([a0].[Id])
ORDER BY [a0].[TypeId]
I had to upgrade EF Core version to 2.1 and LINQ is now translated properly into SQL.
I can't seem to get this query right. Sequel implementation of:
SELECT count(id) FROM users WHERE username = "alpha" AND status = "new"
Here's what I have so far:
db = Sequel.connect('postgres://me:pw#0.0.0.0:5432/dbname)
u = db[:users]
puts "Total users: #{u.count}" # this is correct
puts db.where(:username => "alpha", :status => "new").count
I've tried various direct SQL and that doesn't seem to work either. It smells like this is remedial, but the connectivity is fine, and I can replicate the exact SQL which doesn't come back the same.
You forgot to select the table. You want this:
db[:users].where(username:'alpha', status:'new').count
For SQLite3, this produces the query:
SELECT count(*) AS 'count'
FROM `users`
WHERE ((`username` = 'alpha')
AND (`status` = 'new'))
LIMIT 1
The error message you should have been getting was:
NoMethodError: undefined method `where' for #<Sequel::SQLite::Database: ...>
If you saw this error and read it, it should have let you know that calling db.where was not right.
In addition to making this work with the native Sequel DSL, you can also always run raw sql commands in Sequel.
I'm trying to do this:
SELECT
userId, count(userId) as counter
FROM
quicklink
GROUP BY
userId
HAVING
count(*) >= 3'
In doctrine with the querybuilder, I've got this:
$query = $this->createQueryBuilder('q')
->select('userId, count(userId) as counter')
->groupby('userId')
->having('counter >= 3')
->getQuery();
return $query->getResult();
Which gives me this error:
[Semantical Error] line 0, col 103 near 'HAVING count(*)': Error: Cannot group by undefined identification variable.
Really struggling with doctrine. :(
Your SQL is valid, Your query builder statement is invalid
All cause db will execute that query in following order:
1. FROM $query = $this->createQueryBuilder('q')
2. GROUP BY ->groupby('userId') // GROUP BY
3. HAVING ->having('counter >= 3')
4. SELECT ->select('userId, count(userId) as counter')
So as You can see counter is defined after its use in having.
Its SQL Quirk. You can not use definitions from select in where or having statements.
So correct code:
$query = $this->createQueryBuilder('q')
->select('userId, count(userId) as counter')
->groupby('userId')
->having('count(userId) >= 3')
->getQuery();
return $query->getResult();
Do note repetition in having from select
I am going to answer for people who still have this type of error.
First things first, you seem to have translated a native sql query inside a query builder object. More so, you have named your object as q
$query = $this->createQueryBuilder('q');
What this means, in general, is that every condition or grouping etc you have in your logic should address fields of q: q.userId, q.gender, ...
So, if you had written your code like below, you would have avoided your error:
$query = $this->createQueryBuilder('q')
->select('q.userId, count(q.userId) as counter')
->groupby('q.userId')
->having('counter >= 3')
->getQuery();
return $query->getResult();
I think you are missing the 'from' statement
$query = "t, count(t.userId) as counter FROM YourBundle:Table t group by t.userId having counter >1 ";
return $this->getEntityManager()->createQuery($query)->getResult();
This should work. You can even do left joins or apply where clausules.
you can define HAVING parameter via setParameter() method as well
$qb->groupBy('userId');
$qb->having('COUNT(*) = :some_count');
$qb->setParameter('some_count', 3);
For a LINQ query like:
var entities = from Account p in context.Accounts
where p.LastTimeServerSettingsChanged > p.LastTimeDeviceConnected
select p;
the query that is generated is:
SELECT
[Extent1].[Username] AS [Username],
[Extent1].[LastTimeDeviceConnected] AS [LastTimeDeviceConnected],
[Extent1].[LastTimeServerSettingsChanged] AS [LastTimeServerSettingsChanged]
FROM [dbo].[Account] AS [Extent1]
WHERE [Extent1].[LastTimeServerSettingsChanged] > [Extent1].[LastTimeDeviceConnected]
And this does not work (no results).
And the following also generates the same SQL (hence no results also)
var entities = context.Accounts.Where(k => k.LastTimeServerSettingsChanged > k.LastTimeDeviceConnected).Select(k => k);
My question is why, and how can this query be performed (using LINQ)?
The above code works fine. I was hitting the wrong database and hence was getting the wrong result. GIGO. QED.