The original functional MySQL query that lists all and only the providers that have all the listed tags:
SELECT * FROM provider
INNER JOIN provider_tag
ON provider_tag.provider_id = provider.id AND provider_tag.tag_id in (1, 2)
GROUP BY (provider.id)
HAVING COUNT(*) = 2
Translating to MySQLQuery in Querydsl is straightforward...
MySQLQuery query = new MySQLQuery(conn, dialect);
List<Integer> tagIds = ...;
query.from(provider)
.innerJoin(provider_tag)
.on(providerTag.providerId.eq(provider.id), providerTag.tagId.in(tagIds))
.groupBy(provider.id)
.having(???);
... except for the condition in having.
How do I add COUNT(*) to the query?
EDIT after Timo's 1st correction proposal:
So, the query looks like this:
SearchResults<Tuple> result = query.from(provider)
.innerJoin(providerTag)
.on(providerTag.providerId.eq(provider.id), providerTag.tagId.in(tagIds))
.groupBy(provider.id)
.having(Wildcard.count.eq((long) tagIds.size()))
.listResults(
provider.id,
provider.name);
However, this causes an SQLException Illegal operation on empty result set, if the result set is empty.
My other queries that return an empty result set do not cause exceptions, so I guess I should not need to catch the exception, but there is a problem that should be fixed?
The generated MySQL works perfectly (returns 0 rows), so the problem is not there.
EDIT 2:
The problem was in groupBy(). This seems to work, if one applies the correction shown in the issue.
The querydsl equivalent for COUNT(*) is Wildcard.count.
Related
I use spring boot, and I want to add 1 year to a specific column in mysql database
String queryRecherche = "UPDATE myTable t SET t.dateDebut = DATE_ADD(t.dateDebut, INTERVAL 1 YEAR) WHERE.id = 3 ";
Query query = em.createQuery(queryRecherche);;
query.executeUpdate();
But I get the folowing error :
org.hibernate.query.sqm.ParsingException: line 1:66 no viable alternative at input 'DATE_ADD(t.dateDebut,INTERVAL1'
Have you please any suggestions to do this.
You're using Hibernate 6 (I can tell by the error message), so the correct HQL syntax to use is:
UPDATE MyEntity t SET t.dateDebut = t.dateDebut + 1 year WHERE t.id = 3
You had three errors in your query:
You referred to the name of a table instead of the name of an entity class in the UPDATE clause.
You used the unportable MySQL DATE_ADD function instead of the portable HQL date/time arithmetic described here.
The syntax of your WHERE clause was garbled.
Perhaps you meant for this to be a native SQL query, in which case you called the wrong method of Session. But there's no need to use native SQL for the above query. As you can see, HQL is perfectly capable of expressing that query.
You can use SQL directly, via createNativeQuery, or register a new function as shown in this example to call it from HQL
I am absolutly new in Hibernate and I have the following problem.
I have this standard SQL query:
SELECT count(*)
FROM TID003_ANAGEDIFICIO anagraficaEdificio
INNER JOIN TID002_CANDIDATURA candidatura
ON (candidatura.PRG_PAR = anagraficaEdificio.PRG_PAR AND candidatura.PRG_CAN = anagraficaEdificio.PRG_CAN)
INNER JOIN TID001_ANAGPARTECIPA anagPartecipa ON(anagPartecipa.PRG_PAR = candidatura.PRG_PAR)
INNER JOIN anagrafiche.TPG1029_PROVNUOIST provNuovIst ON (provNuovIst.COD_PRV_NIS = anagPartecipa.COD_PRV_NIS)
WHERE anagraficaEdificio.FLG_GRA = 1 AND provNuovIst.COD_REG = "SI";
This works fine and return an integer number.
The important thing to know is that in this query the only
parameter that can change (inserted by the user in the frontend of a webappplication) is the last one (this one: provNuovIst.COD_REG = "SI").
So, the application on which I am working use Hibernate and the requirement say that I have to implement this query using Hibernate Native SQL, I have found this tutorial:
http://www.tutorialspoint.com/hibernate/hibernate_native_sql.htm
that show this example:
String sql = "SELECT * FROM EMPLOYEE WHERE id = :employee_id";
SQLQuery query = session.createSQLQuery(sql);
query.addEntity(Employee.class);
query.setParameter("employee_id", 10);
List results = query.list();
that, from what I have understand (correct me if I am doing wrong assertion), involves the use of an Employee model class. So th prvious query first define the query (using the :param_name syntax for the parameter), then create an SQLQuery Hibernate object, add the class used for the result, set the previous parameter neam and finally obtain a List (that I think Hibernate create as something like an ArrayList) with the retrieved object.
My problem is that I simply I have to obtain an integer value (because I have a SELECT count(*), so I will obtain an integer value and not a set of rows).
So how can I correctly use the Hibernate Native SQL to implement my SQL query into my Hibernate repository class?
Use SQLQuery.uniqueResult to retrieve a single value from the query:
String sql = "SELECT count(*) ...";
SQLQuery query = session.createSQLQuery(sql);
// set parameters...
int count = ((Number)query.uniqueResult()).intValue();
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.
I want to use spring-batch for retrieving and processing data from a postgres db.
I have a working SQL statement that would give me the full result set (about 400k entries):
private static final String QUERY = "SELECT * FROM MyDataTable ";
Now I want to use the JpaPagingItemReader so that the data is fetched (and written elsewhere) in chunks:
JpaPagingItemReader<MyEntity> reader = new JpaPagingItemReader<>();
reader.setEntityManagerFactory(emf);
reader.setQueryString(QUERY);
But it does not work:
[] 2014-09-17 16:31:58,234 ERROR : QuerySyntaxException: unexpected token: * near line 1, column 8 [SELECT * FROM my_data_table]
I also tried SELECT FROM MyDataTable and SELECT m FROM MyDataTable m without the star. Same result.
So, how can I execute that hql query with spring-batch?
By the way: the query works fine in a sql editor like pgAdmin.
SELECT m FROM MyDataTable m is almost correct (it is valid JPQL query as long as you have entity calles MyDataTable). So, it seems that you don't have entity class named MyDataTable.
As JpaPagingItemReader#setQueryString(String) accepts JPQL queries you should make sure that you have entity class for this table and then you should use its name instead MyDataTable.
By the way - for HQL queries there's HibernatePagingItemReader.
I need to use the LIKE operator into an JPA query. I need to use it for types other then String but the JPA criteria API allows me to add only String parameters. I tried using the .as(String.class) but something fails and also tried calling the CAST function from the underlying Oracle that again fails for unknown reasons to me.
I tried writing the query also in JPQL and it works as expected. This is the query:
SELECT p from CustomerOrder p where p.id like '%62%'
UPDATE:
The query must be built in a generic fashion as it is for filtering, so it needs to be created at runtime. On the query that is already created I tried to add the LIKE clause like this:
query.where(builder.like(selectAttributePath.as(String.class), "%"+filterValue.toString().toLowerCase()+"%"));
But this crashes with this exception:
org.hibernate.hql.internal.ast.QuerySyntaxException: expecting CLOSE, found '(' near line 1, column 156 [select distinct generatedAlias0.id from de.brueckner.mms.proddetailschedact.data.CustomerOrder as generatedAlias0 where cast(generatedAlias0.id as varchar2(255 char)) like :param0]
I executed the same query directly to Oracle using SQLDeveloper, so it should be sound from this point of view. So the problem is the Hibernate is the issue. Any suggestions on how to fix it?
How can I write this query using JPA Criteria?
I fixed the problem by invoking the 'TO_CHAR' function from the underlying Oracle DB and using the LIKE operator like for normal String's.
query.where(builder.like(selectAttributePath.as(String.class), "%" +filterValue.toString().toLowerCase() + "%")
You can try the below code, it might require modifications.
CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery<CustomerOrder> cq = cb.createQuery(CustomerOrder.class);
Root<CustomerOrder> order = cq.from(CustomerOrder.class);
cq.where(cb.like(Long.valueOf(order.get(CustomerOrder_.id)).toString(), "%62%"));
TypedQuery<CustomerOrder> q = em.createQuery(cq);
List<CustomerOrder> results = q.getResultList();