I wanted to perform the Spring JPA repository where wanted to apply the and operation among 2 columns where one column cloud have multiple values in it.
SQL query for the same:
select * from table_name where col1='col1_val' and col2 IN
('col2_val_a','col2_val_b','col2_val_c');
I know that for and operation I can extend the JpaRepository and create the method with like this for:
List<MyPoJoObject> findByCol1AndCol2(String col1_val,String col2_val);
and for IN operation we can use : findByCol2In(Collection<String> col2_val)
But i did not know how i can club both the mentioned JPA default method into one, as per my sql statement mentioned before.
You can use the following method named:
List<MyPoJoObject> findByCol1AndCol2In(String col1_val, Collection<String> col2_val);
On this link repository-query-keywords you can find repository query keywords that you can use and combine them as well.
You can certainly combined both into one method.
List<MyPoJoObject> findByCol1AndCol2In(String col1_val,String[] col2_val);
Try this. I am not sure if it will accept Collection<String>. I will try that and update the answer.
HTH.
If you want to perform this logic for more than two columns then your method name becomes verbose.
Instead of stuck with Spring naming why can't you write your own JPA query.
Example:
#Query("select pojo from MyPoJoObject as pojo where pojo.col1 = :col1_val and pojo.col2 in :col2_val")
List<MyPoJoObject> findByColumns(String col1_val, List<String> col2_val);
Related
I have one table which has all the api audit information - Table name : api_audit
I have one table which has extra information about every api call - Table name : api_audit_info
Inside api_audit I have primary key as "transaction_id".
I want all the data from api_audit table and some data from api_audit_info table.
I have written a custom query like -
#Query(select c from ApiAudit c INNER JOIN ApiAudiInfo t ON c.transactionId = t.msgId)
But the issue is that the result type that I am getting this way contains only ApiAudit type data.
What shall I do to get data from both the tables. Please help.
Note: I am using JpaRepository as I need paginated data.
I am fairly new to Spring boot and JPA so not sure exactly which direction to look to.
Whenever I need to join data from more than 1 table, I am using Jdbi.
Here you have the official documentation:
Remember to include the required dependencies and configure a bean for Jdbi in your project.
Then I create a repository class, POJO and query with all of the information which I need. For example:
select c.transaction_id as transactionId, t.name as name from ApiAudit c INNER JOIN ApiAudiInfo t ON c.transactionId = t.msgId
Here you have some code samples from official documentation
After you map your data to POJO, you can use
public PageImpl(List<T> content, Pageable pageable, long total)
to return paginated data.
There is a big chance that there is a better solution, but this works for me every time.
I'm building REST API connected to ORACLE 11G DB. API sends data to Android client using JSON. To get data I'm using JpaRepository, and #Query annotations.
I want to provide data for charts: number of contracts in years.
I have native SQL query:
select aa.ROK, count(aa.NUMER_UMOWY)
from (select distinct NUMER_UMOWY, ROK from AGR_EFEKTY) aa
group by aa.ROK order by aa.ROK
Result of query using SQL Developer look like this:
I tried to get result using native query:
But result is always like this:
or error depending what I try.
Is it possible to obtain list of count() results using #Query?
If not, what should I use?
Thanks in advance :-)
I think What you are trying to use here is spring data projection.
As mentioned in the reference doc:
Spring Data query methods usually return one or multiple instances of
the aggregate root managed by the repository. However, it might
sometimes be desirable to create projections based on certain
attributes of those types. Spring Data allows modeling dedicated
return types, to more selectively retrieve partial views of the
managed aggregates.
and particularly closed projection where all accessor methods match the target attributes. In your case the count is not an attribute of your aggregate.
To perform what you want you can use constructor as follow :
class ContractsDto{
private String rok;
private int count;
public ContractsDto(String rok, int count) {
this.rok=rok;
this.count =count;
}
// getters
}
The query will be:
#Query(value = "select new ContractsDto(aa.rok , /*count */) from fromClause")
List<ContractsDto> getContractsPerYear();
I use spring data JPA. I need in my repository request to load only collection of concrete properties colors:
#Query(value = "SELECT cd.color FROM CalendarDetails cd where cd.userCalendar.userId = :userId")
List<String> findCalendarColorsByUserWithDuplicates(#Param("userId") Long userId);
Provided solution works correctly.
I want simplify it using spring approach to load collection of the repository objects I'd use (repository public interface CalendarDetailsRepository extends JpaRepository<CalendarDetails, Long>):
List<CalendarDetails> findByUserCalendarUserId(#Param("userId") Long userId);
But I need collection of colors! Trying
List<String> findColorByUserCalendarUserId(Long userId);
I get collection of CalendarDetails
Is it possible to improve my last request following spring data approaches to load list of colors?
You can try special Projection mechanisms that Spring Data provides. It will allow you not only to optimize your queries but also to make it with pure java without using #Query.
There are a lot of ways to
make it, but I would recommend the following.
You add an interface that contains getters for the properties that you need to take from entity:
public interface ColorOnly {
String getColor();
}
Then you return the list of this interface' objects:
List<ColorOnly> findColorByUserCalendarUserId(Long userId);
To use the colours from the interface, you just invoke getColor method. You may consider simplifying it with Java 8 streams and map conversions. BTW, this one will only query colour. No other fields will be included into the query Hibernate produces.
Try to add All
findAllByUserCalendarUserId(Long userId);
BTW, IntelliJ IDEA provide very deep support of JPA repositories, so it's prevent a lot of possible issues when you create queries like this one
I'm writing couchbase repository using Spring module and I'm trying to add my own implementation of count method using N1QL query:
public interface MyRepository extends CouchbaseRepository<Entity, Long> {
#Query("SELECT count(*) FROM default")
long myCount();
}
But it doesn't work:
org.springframework.data.couchbase.core.CouchbaseQueryExecutionException: Unable to retrieve enough metadata for N1QL to entity mapping, have you selected _ID and _CAS?
So my question is: how can I write counting query using spring-data-couchbase?
I cannot find anything about this in spring documentation. link
This exception happens because the #Query annotation was designed with the use-case of retrieving entities in mind. Projections to a scalar like count are uncovered corner cases as of RC1. Maybe I can think of some way of adding support for it through explicit boolean flag in the annotation?
Unfortunately I was unable to find a workaround. I was trying to come up with a custom repository method implementation but it appears support for it is broken in 2.0.0-RC1 :(
edit:
The use case of simple return types like long, with a SELECT that only uses a single aggregation, should work so this is a bug/improvement. I've opened ticket DATACOUCH-187 in the Spring Data JIRA.
#Query("SELECT count(*) , META(default).id as _ID, META(default).cas as _CAS FROM default")
Change your query to this one.
Use this query :
#Query("SELECT count(*) as count FROM #{#n1ql.bucket} WHERE #{#n1ql.filter} ")
long myCount();
I'm just getting to grips with JPA in a simple Java web app running on Glassfish 3 (Persistence provider is EclipseLink). So far, I'm really liking it (bugs in netbeans/glassfish interaction aside) but there's a thing that I want to be able to do that I'm not sure how to do.
I've got an entity class (Article) that's mapped to a database table (article). I'm trying to do a query on the database that returns a calculated column, but I can't figure out how to set up a property of the Article class so that the property gets filled by the column value when I call the query.
If I do a regular "select id,title,body from article" query, I get a list of Article objects fine, with the id, title and body properties filled. This works fine.
However, if I do the below:
Query q = em.createNativeQuery("select id,title,shorttitle,datestamp,body,true as published, ts_headline(body,q,'ShortWord=0') as headline, type from articles,to_tsquery('english',?) as q where idxfti ## q order by ts_rank(idxfti,q) desc",Article.class);
(this is a fulltext search using tsearch2 on Postgres - it's a db-specific function, so I'm using a NativeQuery)
You can see I'm fetching a calculated column, called headline. How do I add a headline property to my Article class so that it gets populated by this query?
So far, I've tried setting it to be #Transient, but that just ends up with it being null all the time.
There are probably no good ways to do it, only manually:
Object[] r = (Object[]) em.createNativeQuery(
"select id,title,shorttitle,datestamp,body,true as published, ts_headline(body,q,'ShortWord=0') as headline, type from articles,to_tsquery('english',?) as q where idxfti ## q order by ts_rank(idxfti,q) desc","ArticleWithHeadline")
.setParameter(...).getSingleResult();
Article a = (Article) r[0];
a.setHeadline((String) r[1]);
-
#Entity
#SqlResultSetMapping(
name = "ArticleWithHeadline",
entities = #EntityResult(entityClass = Article.class),
columns = #ColumnResult(name = "HEADLINE"))
public class Article {
#Transient
private String headline;
...
}
AFAIK, JPA doesn't offer standardized support for calculated attributes. With Hibernate, one would use a Formula but EclipseLink doesn't have a direct equivalent. James Sutherland made some suggestions in Re: Virtual columns (#Formula of Hibernate) though:
There is no direct equivalent (please
log an enhancement), but depending on
what you want to do, there are ways to
accomplish the same thing.
EclipseLink defines a
TransformationMapping which can map a
computed value from multiple field
values, or access the database.
You can override the SQL for any CRUD
operation for a class using its
descriptor's DescriptorQueryManager.
You could define a VIEW on your
database that performs the function
and map your Entity to the view
instead of the table.
You can also perform minor
translations using Converters or
property get/set methods.
Also have a look at the enhancement request that has a solution using a DescriptorEventListener in the comments.
All this is non standard JPA of course.