I'm trying to filter data using query by example. It's working for entities and primitives, but not for projections. Do You know if such functionality available in Spring Data Jpa?
At this moment it's not implemented in Spring Data Jpa 2.1.0.RC2, but as workaround it's possible to use extension like specification-with-projection
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I have a CRUD based application, which uses Spring Boot REST Services and JPA. For JPA we have POJO objects mapped to RBMS - PostgreSQL.
Some of my pages require data to be fetched using joins of multiple POJO objects. I just wanted to know what is a good architectural practice to do the same. Following are some of the options i have been informed of, but not sure what are the pros and cons of each especially for a large data volume application.
Use Transient Variables in POJOs and use JPA joins
Use additional Spring View Objects to combine POJOs
Write native/HQL to join tables/POJOs
Any insight would be helpful. If any more details required from me, would be glad to provide.
I think it's better to go with Entity Mappings.
This will enable you to easily fetch the parent and its nested entities using either JPA methods or using hibernate.
You can also specify the fetch type to actually control the behaviour of this fetch.
In case, you are looking for any complex joins or fetch patterns, Entity Graphs and HQL will be very useful.
I am building an application with the spring boot framework. I can easily use spring data to query data from db, but is there anyway I can send the merge query like below, instead of first creating thousands of object and save them like this post.
USING PERIODIC COMMIT
LOAD CSV WITH HEADERS FROM
'file:///existed_file.csv' as line
WITH line
MERGE (n:Item {itemId: line.id)})
You can use the #Query to on a repository, or use the OGM session.query to directly execute your Cypher statement.
However, SDN is not suited for data import in general (see When not to use SDN).
I have to use SOQL queries within a Spring Data Repository, Is there a way to do so by using #Query annotation ? If not is there a alternative way ?
As far as I know salesforce doesn't expose the table structures. Rather they expose their objects and you can write queries on them. spring-data-jpa is used on top of an entity framework like hibernate. Unless you have entity objects mapped to actual database tables, spring-data-jpa is not useful.
The best way would be to use a query builder like jooq and construct SOQL queries easily using query builders.
I have some entities. I want to get joining result from those entities.I have to use Hibernate and spring data. How can I get result by joining those entities? I have not found any proper tutorial or example.
I am new to spring and hibernate .
I use the spring data jpa framework to easily handle the whole dao stuff and it is awesome. A couple of days ago I test the repo populator functionality of spring data jpa and it also worked pretty smooth, but is it possible to handle relationships ? not the cascade persist types, they are easy to handle ... I mean those one to one relationships where the data for this type is provides by another json file.
Hmm I hope it is a bit understandable what I want to do. Did anyone has an idea to handle this with spring data jpa?
Thanks for any kind of help and have a good weekend :)