I have a query like the following:
Select new mypackage.MyClass( u, max(sc.serviceDate))
from Unit u left join u.serviceCalls sc
where u.organization.key = :organizationKey
So, my mapping is that I have a Unit, which has a collection of ServiceCalls (FetchType.LAZY), and also has an organization. Each ServiceCall has a serviceDate.
In my query, I would like to select the entire Unit, but not all of the serviceCalls. I would like to fetch the most recent serviceDate if one exists.
Attempting to execute the query through eclipselink on postgres gets me the following (I removed some selected fields from the query output)
Internal Exception: org.postgresql.util.PSQLException: ERROR: column "t0.key" must appear in the GROUP BY clause or be used in an aggregate function
Position: 8
Error Code: 0
Call: SELECT t0.KEY, MAX(t1.service_date) FROM unit t0 LEFT OUTER JOIN service_call t1 ON (t1.unit_key = t0.KEY), organization t2 WHERE ((t2.KEY = ?) AND (t2.KEY = t0.organization_key))
It looks like max is being applied across all service calls instead of getting me the max for each unit. Is there a way to do this or am I going to have to just getch all the service calls and get the max that way?
Do you need a group by u at the end?
Related
I have a record that I need to do some validation on. This record can potentially have multiple children. I need to create a collection (I was planning on using a standard list) containing the ID of every child record but this needs to be recursive (i.e. each child record can also have child records of its own, and I need each of those IDs as well, ad infinitem).I'm using MSSQL Server for my DB but I'm not too sure how I would structure the necessary SQL query.
This is what I have tried;
DECLARE #Id VARCHAR(30) = '[Record Id]';
WITH cte AS
(
SELECT record.id, record.parentid
FROM records r
WHERE id = #Id
UNION ALL
SELECT record.id, wo.parentid
FROM records r JOIN cte c ON wo.parentid = c.id
)
SELECT id
FROM cte;
I get the following error:
The statement terminated. The maximum recursion 100 has been exhausted before statement completion.
I need to build SQL query with common table expression using QueryDSL:
WITH cte AS (
SELECT DISTINCT BUSINESS_ID FROM BUSINESS WHERE MERCHANT_CODE like ?
)
SELECT t0.*
FROM PAYMENT t0
LEFT JOIN cte t1 ON t0.PAYER = t1.BUSINESS_ID
LEFT JOIN cte t2 ON t0.PAYEE = t2.BUSINESS_ID
WHERE (t1.BUSINESS_ID IS NOT NULL OR t2.BUSINESS_ID IS NOT NULL)
I have two JPA entities (Payment, Business).
This is how I implemented that:
String merchantCode = "abcd%";
QPayment payment = QPayment.payment;
QBusiness business = QBusiness.business;
QBusiness cte = new QBusiness("cte");
QBusiness merchant1 = new QBusiness("t1");
QBusiness merchant2 = new QBusiness("t2");
Configuration configuration = new Configuration(new OracleTemplates());
new JPASQLQuery<>(entityManager, configuration)
.with(cte,
JPAExpressions.selectDistinct(business.businessId).from(business)
.where(business.merchantCode.like(merchantCode)))
.select(payment)
.from(payment)
.leftJoin(cte, merchant1).on(payment.payer.eq(merchant1.businessId))
.leftJoin(cte, merchant2).on(payment.payee.eq(merchant2.businessId))
.where(merchant1.businessId.isNotNull()
.or(merchant2.businessId.isNotNull()));
And the problem is that during leftJoin it doesn't treat cte as a link, instead it inserts table name and two aliases: LEFT JOIN BUSINESS cte t1 ON .... I tried different templates – didn't help.
Am I doing something wrong or it's a QueryDSL bug?
JPQL doen't support CTEs, as we can see in grammar. And querydsl works over JPQL. CTEs are pretty vendor-specific, so you'll have to do one of following:
Rewrite query to be JPA-compatible
Use JPA native query
Query sql with querydsl (actually I don't remember if it supports CTEs)
From all above I would chose the 2nd option. Making native queries doen't harm your code. It makes your code more performant.
Take a good look at the tutorial
QCat cat = QCat.cat;
QCat mate = new QCat("mate");
QCat kitten = new QCat("kitten");
query.from(cat)
.innerJoin(cat.mate, mate)
.leftJoin(cat.kittens, kitten)
.list(cat);
You will want to .leftjoin(cte.merchant1, merchant1).on(...) or whatever the corresponding field is called in the parent "cte".
Basically you need to name the field which you want to join. Just stating the meta model does not suffice as there is no way of telling what you actually want. You can see it in your code (as well in the tutorial's kitten example): you have two Merchant you want to join to the cte, so which one is which.
The .on()-clause just states the conditions under which a join is valid, like you could place filters there.
.
I'm using Spring Boot 1.5.2 and the following #Query:
#Query(value = "SELECT m FROM Message m WHERE m.from.userId = :myId OR m.to.userId = :myId GROUP BY m.from.userId, m.to.userId ORDER BY m.date DESC")
List<Message> chatOverview(#Param("myId") final Long myUserId);
The intention of the query is to create a chat messenger overview, where you see the last message of each conversation you had. It works fine for me in dev, but in production (newer MySQL database version) I get this error:
java.sql.SQLSyntaxErrorException: Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'message0_.message_id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
I read in this thread what the reason for this change was, however I couldn't find a way to fix this with JPA / Spring. I cannot change any settings in the production MySQL database and I would like to avoid any upgrading in Spring either. How can I fix my query?
Here is the definition and purpose of the GROUP BY (see section 4.7) clause:
The GROUP BY construct enables the aggregation of result values according to a set of properties.
That means it is used only if you're aggregating (sum, avg, max, min, ...) the value(s) of a field(s). But in your case I don't see any aggregation function. So just remove the GROUP BY clause and everything should be fine:
SELECT m FROM Message m WHERE m.from.userId = :myId OR m.to.userId = :myId ORDER BY m.date DESC
Grouping on userId doesn't make sense too because all the entities returned by this query will have the same value for this field.
I'm working with JPA CriteriaBuilder, CriteriaQuery etc. and static metamodels for typesafe queries, like here for example: click.
I have 3 tables: Client, Package, Vegetable.
Every client has 1 or more packages, and those packages contain multiple vegetables.
What I have now:
CriteriaBuilder builder = entityManager.getCriteriaBuilder();
CriteriaQuery<Client> query = builder.createQuery(Client.class);
Root<Client> root = query.from(Client.class);
ListJoin<Package, Vegetable> join = root.join(Client_.packages).join(Package_.vegetables);
TypedQuery<Client> typedQuery = entityManager.createQuery(query);
return typedQuery.getResultList();
The ListJoin I added recently. Point is what Hibernate does: generates the whole select for all fields in Client class from the Client table inner joined with Package and Vegetable, but it doesn't actually selects those fields from joined tables. It gets every package by ID and then every vegetable by ID, thus doing n+1 selects.
Without the ListJoin it doesn't inner join those tables, but I'm working on it right now so I added those joins. Now I want to select all the fields from those classes so I get whole object hierarchy with 1 select. I tried doing something with projections like in the link I gave in Projecting the result chaper, but I have no idea how to connect that with ListJoin.
Is that even possible in this situation? When I run this query on database (with manually added all the fields from joined tables) it works fine, but would Hibernate handle that? And if so - how to project the result so it selects all the fields from 3 tables joined together and constructs whole object hierarchy, all with 1 select?
//Edit: managed to retrieve all packages with a single query, but going further raises exception:
Root<Client> root = query.from(Root.class);
ListJoin<Client, Package> join = root.join(Client_.packages);
ListJoin<Package, Vegetable> secondJoin = join.join(Package_.vegetables);
root.fetch(Client_.packages);
Naturally, I tried to add: join.fetch(Package_.vegetables); but it raises the org.hibernate.QueryException: query specified join fetching, but the owner of the fetched association was not present in the select list, no idea what is that.
As to the latest comment: gonna try that now.
//Edit2: I added 2 fetches (couldn't cast them to Join like in that answer, compiler errors):
Fetch<Client, Package> join = root.fetch(Client_.packages);
Fetch<Package, Vegetable> secondJoin = join.fetch(Package_.vegetables);
It raises org.hibernate.loader.MultipleBagFetchException: cannot simultaneously fetch multiple bags, known error I guess so at least got something to search for.
//Edit3: Changed it both to Sets and it works, thanks, couldn't have done it without the Fetch instead of Join suggestion, seems kinda unintuitive to me.
I am using jpa native query , but its not returning values from salias it returns values from S
Query query = em.createNativeQuery("Select S.\"MESSAGE\",S.\"DESTINATION\",S.\"SENT_DATE\",S.\"CLIENT_TRACKING_ID\",S.\"MESSAGE_COST\",S.\"sTId\",salias.\"STATUS\",salias.timeDate from \"sent_sms_view\" S left join ( Select Distinct on (\"SMS_ID\") R.\"SMS_ID\",R.\"STATUS\",R.timeDate from \"sms_receipt_view\" R Order By R.\"SMS_ID\",R.timeDate Desc)As salias on S.\"SYSTEM_TRACKING_ID\"=salias.\"SMS_ID\" where S.Id_systemUser=:systemUser and S.\"CLIENT_TRACKING_ID\"=:cTId");
query.setParameter("cTId", cTId);
query.setParameter("systemUser", systemUser);
if (query.getResultList().size() > 0){
List<Object> resultat = query.getResultList();
This is the Postgres query and it works fine
Select S."MESSAGE",S."DESTINATION",S."SENT_DATE",S."CLIENT_TRACKING_ID",S."MESSAGE_COST",S."sTId" ,salias."STATUS",salias.timeDate
from "sent_sms_view" S
left join ( Select Distinct on ("SMS_ID") R."SMS_ID",R."STATUS",R.timeDate from "sms_receipt_view" R Order By R."SMS_ID",R.timeDate Desc)As salias
on S."SYSTEM_TRACKING_ID"=salias."SMS_ID"
where S.Id_systemUser='101' and S."CLIENT_TRACKING_ID" ='abda';
Can anyone tell me what i am doing wrong.
I'm only guessing what you might be trying to do, since you haven't told us, but here's how I'm guessing it should probably look like:
SELECT S."MESSAGE", S."DESTINATION", S."SENT_DATE", S."CLIENT_TRACKING_ID", S."MESSAGE_COST", S."sTId", salias."STATUS", salias.timeDate
FROM "sent_sms_view" S
INNER JOIN "sms_receipt_view" AS salias on (S."SYSTEM_TRACKING_ID" = salias."SMS_ID")
WHERE S.Id_systemUser=:systemUser AND S."CLIENT_TRACKING_ID"=:cTId
However I don't see why you would have numerical IDs, such as Id_systemUser stored as strings. In fact that variable name indicates horrible database design. CamelCasing combined with underscores is something you must categorically avoid.
And you must never call query.getResultList() twice if you're looking for the same results. Simply store the List to a local variable and then use it.