I have two entities, course and subject as follows,
#Document(collection = "course")
public class Course implements Serializable {
{
...........
#Field("course_name")
private String courseName;
#Field("subjectIds")
private List<String> subjectIds;
...
}
#Document(collection = "subject")
public class Subject implements Serializable {
private static final long serialVersionUID = 1L;
#Id
private String id;
#Field("subject_name")
private String subjectName;
...................
}
here "Course" contains the list of Ids of Subject.
So , I have a subject Id say ("59ce80a4a2e7f329eccac601"), I need to find all the courses where this subject id will be present in the list of subjectIds property of Course.
Is there any way I can write this in query.
I am using mongorepository of spring
MongoDB native query:
db.course.find({subjectIds: { $elemMatch: { $eq: "59ce80a4a2e7f329eccac601"}}})
A corresponding Spring Data MongoDB Query:
#Query("{'subjectIds': {\$elemMatch: {\$eq: ?0}}}")
Related
I have a Springboot Application with Repositories having Spring Data JPA Queries like findOne, findAll and also derived ones like findByID or findByName etc.
What I want to achieve is multitenancy. All entities have an "account_id" column which holds the tenant.
How do I add a filter like "account_id" to all the queries metioned above without using derived queries that contains those name slike findIdAndAccountid (which would be findone)
#Repository
public interface CategoryRepository extends JpaRepository<Category, Long> {
Category findByName(String name);
}
Here's the corresponding entity
#Entity
#Table(name = "unit")
#Data
public class Unit {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
I know most people use schemas as tenant separation but that's impossible for me. Is there a way (I didn't find one) to add such a tenant filter condition on those queries without writing NamedQueries or using DerivedQueries. An elegeant solution like annotate the repository or entity or maybe the queries that all queries should add the additional filter "account_id"?
You can add Where clause on your Entity classes (Didnt had time to test )
#Entity
#Table(name = "unit")
#Data
#Where(clause = "account_id= :account_id")
public class Unit {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
Update and Solution
1. Create a Filter & FilterDef on the entity like so
#FilterDef(name="accountFilter", parameters=#ParamDef( name="accountId", type="long" ) )
#Filters( {
#Filter(name="accountFilter", condition=":accountId = account_id")
} )
public class Category {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
enable filtering in the controller by autowiring entitymanager, writing a method to enable the filter and activate the filter in #ModelAttribute for each request
#RestController
#RequestMapping(path = "/categories",produces = MediaType.APPLICATION_JSON_VALUE )
public class CategoryController {
private final CategoryRepository repository;
#Autowired
private EntityManager entityManager;
CategoryController(CategoryRepository repository) {
this.repository = repository;
}
private void activateFilter() {
Session session = entityManager.unwrap(Session.class);
Filter filter = session.enableFilter("accountFilter");
filter.setParameter("accountId", Long.valueOf(TenantContext.getCurrentTenant()));
}
#ModelAttribute
public void initFilter() {
activateFilter();
}
... your rest methods here
}
I want to do a join between Timesheet:
#Data
#AllArgsConstructor
#NoArgsConstructor
#Document(collection = TIMESHEET_COLLECTION)
public class Timesheet {
#Id
private ObjectId id;
private ObjectId employeeId;
private LocalDate date;
private String occupationTitle;
private BigDecimal salary;
private List<TimesheetEntry> entries;
}
and Employee (as embedded document):
#Data
#AllArgsConstructor
#NoArgsConstructor
#Document(collection = Employee.EMPLOYEE_COL)
public class Employee {
#Id
private ObjectId id;
private String registry;
private String cpf;
private String firstName;
private String lastName;
private String nickname;
private String phone;
private LocalDate dateOfBirth;
private LocalDate admissionDate;
private EmployeeOccupation occupation;
private EmployeePaymentPreferences paymentPreferences;
private Map<String, String> equipmentPreferences;
private Boolean active;
}
So I have this aggregation query, with match, lookup, unwind and projection operations.
Aggregation aggregation = Aggregation.newAggregation(matchTimesheetFilter(timesheetFilter), lookupEmployee(), unwindEmployee(), projectEmployee());
There are lookup and unwind implementations. I'm unwinding because employee should be a single object, not an array.
private LookupOperation lookupEmployee(){
return LookupOperation.newLookup()
.from("employee")
.localField("employeeId")
.foreignField("_id")
.as("employee");
}
private UnwindOperation unwindEmployee(){
return Aggregation.unwind("employee");
}
It returns successfully a Timesheet document with a embedded Employee document. The point is: I don't want all data from employee. I only want a few fields.
So, I tried to exclude unwanted fields from employee, using my projection operation:
private ProjectionOperation projectEmployee() {
return Aggregation.project().andExclude("employee.nickname", "employee.firstName", "employee.fullName");
}
It didn't work. My embedded employee is still being returned with all fields. However I can successfully exclude fields from Timesheet, if I do something like this:
private ProjectionOperation projectEmployee() {
return Aggregation.project().andExclude("startDate", "endDate");
}
How can I project custom fields from a document embedded through a lookup operation?
i think you need to exclude "employee.nickname", "employee.firstName", "employee.fullName", instead of "nickname", "firstName", "fullName"
Try this:
private ProjectionOperation projectEmployee() {
return Aggregation.project().andExclude("employee.nickname", "employee.firstName", "employee.fullName");
}
i did it this way (not sure if it's right but it works):
private LookupOperation lookupEmployee(){
return LookupOperation.newLookup()
.from("employee")
.localField("employeeId")
.foreignField("_id")
.as("employeeLookup");
}
no unwind used
Aggregation.project().and("employeeLookup.firstName").as("employee.firstName")
I have been learning myself MongoDB implementation in Spring Boot.
However, I came into a problem with complex queries.
I cannot find any right solution for how to implement complex queries to MongoDB from Spring boot.
I am querying the database with MongoRepository interface implementation.
Let's say that I have three collections:
Person - 1 Person can have many Pets.
Pet - 1 Pet can have 1 PetToy and 1 Person who owns him.
PetToy - 1 PetToy can belong to 1 Pet.
POJO classes are bellow
What do I want to achieve?
I want to make a query, which would be returned me a Person, whose Pet has a Toy (PetToy) with the name "Teddy".
I could not have found a way how to do it. Furthermore, is it the best practice to even use such complex queries, or is it better to write more of little ones in MongoDB?
POJOs:
#Document
#Data
#ToString
public class Person {
#Id
private String id;
private String firstname;
private String lastname;
private int age;
#DBRef
private Pet pet;
}
#Document
#Data
#ToString
public class Pet {
#Id
private String id;
private String name;
private int age;
#DBRef
private List<PetToy> toys;
}
#Document
#Data
#ToString
public class PetToy {
#Id
private String id;
private String name;
}
I have tried to use MongoRepositories; however, I was not able to make the complex query.
How can one write such a query to a MongoDB from Spring Boot?
Thank you very much in advance.
If you can use embedded attributes, the class model should be:
#Document
#Data
#Builder
public class Person {
#Id
private String id;
private String firstName;
private String lastName;
private int age;
private List<Pet> pets;
}
#Data
#Builder
public class Pet {
private String name;
private int age;
private List<PetToy> toys;
}
#Data
#Builder
public class PetToy {
private String name;
}
The repository with the method that achieves what you want:
public interface PersonRepository extends MongoRepository<Person, String> {
List<Person> getByPetsToysName(String name);
}
The getByPetsToysName method basically navigate between Person's attributes Person->pets->toys->name. More info here.
An example
#Configuration
#EnableMongoRepositories
public class TestMongo implements CommandLineRunner {
private final PersonRepository repository;
public TestMongo(PersonRepository repository) {
this.repository = repository;
}
#Override
public void run(String... args) throws Exception {
repository.save(Person.builder()
.firstName("John")
.lastName("Doe")
.age(20)
.pets(Stream.of(Pet.builder()
.name("Ursa")
.age(1)
.toys(Stream.of(PetToy.builder()
.name("Teddy")
.build())
.collect(Collectors.toList()))
.build())
.collect(Collectors.toList()))
.build());
repository.save(Person.builder()
.firstName("Phillip")
.lastName("Larson")
.age(21)
.pets(Stream.of(Pet.builder()
.name("Bella")
.age(5)
.toys(Stream.of(PetToy.builder()
.name("Lolo")
.build())
.collect(Collectors.toList()))
.build())
.collect(Collectors.toList()))
.build());
List<Person> persons = repository.getByPetsToysName("Teddy");
System.out.println(persons.size());
List<Person> persons1 = repository.getByPetsToysName("Lolo");
System.out.println(persons1.size());
}
}
Logs:
find using query: { "pets.toys.name" : "Teddy" } fields: Document{{}} for class: class Person in collection: person
If you want more complex queries you can to take a look at the Spring Data MongoDB docs.
Perform a search on DisabScreenRequest and fetch its child details also. Using DTO projections using a Constructor Expression and JPQL.
The parent entity with a child table.
#Entity
#Table(name = "SCREEN_REQUEST")
public class DisabScreenRequest implements Serializable {
private static final long serialVersionUID = 1L;
#Id
private long requestId;
#Column(name = "CIVILID")
private Long civilId;
#ManyToMany()
#JoinTable(name = "_DISAB_SCREEN_REQ_DETAILS", joinColumns = {
#JoinColumn(name = "REQUEST_ID") }, inverseJoinColumns = { #JoinColumn(name = "DISABILTY_TYPE_ID") })
private Set<DisabMaster> disabilities = new HashSet<DisabMaster>();
public DisabScreenRequest() {
}
}
This is the disability table.
#Entity
#Table(name="DISAB_MASTER")
#Immutable
public class DisabMaster implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name="DIS_TYPE_ID")
private long disabilityTypeId;
#Column(name="DIS_TYPE_DESC")
private String disTypeDesc;
public DisabMaster() {
super();
}
}
Had to fetch all the requests along with the disability for each request.
Search DTO(using this I had other joins to add other than one mentioned here).
public class RequestSearchDto {
private long requestId;
private Long civilId;
private Set<DisabMaster> disabilities;
public RequestSearchDto() {
super();
}
public RequestSearchDto(long requestId, Long civilId) {
super();
this.requestId = requestId;
this.civilId = civilId;
}
public RequestSearchDto(long requestId, Long civilId, Set<DisabMaster> disabilities) {
super();
this.requestId = requestId;
this.civilId = civilId;
this.disabilities = disabilities;
}
}
This is my JPQL query
public interface ReposJPQL {
public String GET__REQUEST = "SELECT DISTINCT new org.test.RequestSearchDto "
+ "(dsr.requestId, dsr.civilId, dsr.disabilities)"
+ " FROM DisabScreenRequest dsr WHERE 1=1 ";
}
This will get an
org.hibernate.exception.SQLGrammarException: could not extract ResultSet.
What Iam I doing wrong here, how can I fetch the child table data ?
Let me know if you need any info
Stack trace :
Caused by: java.sql.SQLException: ORA-00936: missing expression
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:113)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:331)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:288)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:754)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:219)
at oracle.jdbc.driver.T4CPreparedStatement.executeForDescribe(T4CPreparedStatement.java:813)
at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1051)
at oracle.jdbc.driver.T4CPreparedStatement.executeMaybeDescribe(T4CPreparedStatement.java:854)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1156)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3415)
at oracle.jdbc.driver.OraclePreparedStatement.executeQuery(OraclePreparedStatement.java:3460)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:60)
If you need to fetch parent entity with a collection of its nested child entities you can use this simple approach using #EntityGraph annotation or JPQL with join fetch:
#Entity
public class Parent {
//...
#OneToMany
private List<Child> children;
}
#Entity
public class Child {
//...
}
interface ParentRepo extends JpaRepository<Parent, Integer> {
// with #EntityGraph
#EntityGraph(attributePaths = "children")
#Override
List<Parent> findAll();
// or manually
#Query("select distinct p from Parent p left join fetch p.children")
List<Parent> findWithQuery();
}
Note to use distinct in your query to avoid duplicate records.
Example: duplicate-parent-entities
More info: DATAJPA-1299
AFAIK, you can't use constructor expression which take a Collection.
See the JPA 2.2 Spec, section 4.14 BNF, read about the constructor expression:
constructor_expression ::=
NEW constructor_name ( constructor_item {, constructor_item}* )
constructor_item ::=
single_valued_path_expression |
scalar_expression |
aggregate_expression |
identification_variable
This is a perfect use case for Blaze-Persistence Entity Views.
I created the library to allow easy mapping between JPA models and custom interface defined models, something like Spring Data Projections on steroids. The idea is that you define your target structure the way you like and map attributes(getters) via JPQL expressions to the entity model. Since the attribute name is used as default mapping, you mostly don't need explicit mappings as 80% of the use cases is to have DTOs that are a subset of the entity model.
A mapping for your model could look as simple as the following
#EntityView(DisabScreenRequest.class)
interface RequestSearchDto extends Serializable {
#IdMapping
long getRequestId();
Long getCivilId();
Set<DisabMaster> getDisabilities();
}
Querying is a matter of applying the entity view to a query, the simplest being just a query by id.
RequestSearchDtodto = entityViewManager.find(entityManager, RequestSearchDto.class, id);
But the Spring Data integration allows you to use it almost like Spring Data Projections: https://persistence.blazebit.com/documentation/1.4/entity-view/manual/en_US/#spring-data-features
I have a entity (declared with 2 way)(some not influencing code part are ommited for readability)
Entity version 1.
#Entity
public class Article {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
private String name;
#Formula("(SELECT COUNT(w.id) FROM stock s LEFT JOIN warehouse w ON s.id=w.stock_id WHERE s.article_id = id)")
private int variants;
public int getVariants() {
return variants;
}
}
Entity version 2.
#Entity
public class Article {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
private String name;
#Transient
private int variants;
#Access(AccessType.PROPERTY)
#Formula("(SELECT COUNT(w.id) FROM stock s LEFT JOIN warehouse w ON s.id=w.stock_id WHERE s.article_id = id)")
public int getVariants() {
return variants;
}
}
respective DTO and ArticleMapper - MapStruct
#JsonIgnoreProperties(ignoreUnknown = true)
public class ArticleDTOCommon {
private Long id;
private String name;
}
#JsonIgnoreProperties(ignoreUnknown = true)
public class ArticleDTO {
private Long id;
private String name;
private int variants;
}
#Mapper(componentModel = "spring", uses = {})
public interface ArticleMapper{
ArticleDTO toDto(Article article);
ArticleDTOCommon toDtoCommon(Article article);
}
I have a #Service layer on which how i know Hibernate creates it's proxy(for defining which field is fetch or not fetch) and transactions are occurs.
#Service
#Transactional
public class ArticleService {
#Transactional(readOnly = true)
public List<ArticleDTO> findAll() {
return articleRepository.findAll()
stream().map(articleMapper::toDto).collect(Collectors.toList());
}
#Transactional(readOnly = true)
public List<ArticleDTO> findAllCommon() {
return articleRepository.findAll()
stream().map(articleMapper::toDtoCommon).collect(Collectors.toList());
}
}
It works fine with fetching Related entity but
Problem is (fetching #Formula annotated field) when I am looking executed query on log it fetchs all time variants #Formula annotated query not depending on respective DTO.
But it must be ignored on toDtoCommon - i.e. It must not fetch variants field -> because when mapping Article to ArticleDtoCommon it not uses getVariant() field of Article. I have tried multiple ways as mentioned above.
I can solve it with writing native query(for findAllCommon() method) and map respectivelly with other way... But I want to know that how we can solve it with ORM way and where is problem.
Manupulating #Access type is not helping too.
Thanks is advance.