Here down my code:
long contentCount = studentRepository.countBySubjectIdAndStudentTypeAndDepartmentIdIn(subjectId, studentType, departmentIds);
Repository
public interface StudentRepository extends MongoRepository<Student, String> {
long countBySubjectIdAndStudentTypeAndDepartmentIdIn(String subjectId, String studentType, List<String> departmentIds);
}
Here I have 8 records for subjectId I Passed and 8 records for studentType Passed here. But there are only 3 records for departmentIds I passed. But here this query returns 8 instead of 3.
Related
I am writing Spring Boot Data JPA application and I have following situation:
I have 2 database queries fetching from same table but they are fetching different columns and data based on their WHERE clauses. For example:
SELECT CAR_TYPE, CAR_MODEL, CAR_YEAR, ACCIDENT_YEAR, BUY_DAY FROM CAR WHERE ACCIDENT_YEAR IS NULL
, and
SELECT CAR_MODEL, CAR_YEAR FROM CAR WHERE CAR_YEAR >= CURRENT_YEAR
As you can see these 2 queries (whose results will be exposed through 2 different API points) reference the same table CAR, but return different fields and have different WHERE clauses.
I know in JPA, I have to create an entity CarEntity like:
#Entity
#Table(name = "CAR")
public class CarEntity {
// I can only have fields from one or the other query
// here, so I guess I have to have 2 of these
}
, but my problem is that this entity needs to apply for the 2 different queries (with different fields returned, different data, different WHERE clauses).
So, it looks like I have to have actually 2 CarEntity classes. But, I am not sure how to make these 2 CarEntities so they both reference the same table CAR?
You can do by using projection that basically you define an interface with field methods which you want to get them. Projections
#Entity
public class Car implement CarSummary { // if you want you can implement JIC
private UUID id;
private String carType;
private String carModel;
private LocalDateTime carYear;
//getters and setters
}
public interface CarSummary {
String getCardModel();
String getCarYear();
}
Then on your query.
public interface CarRepository extends Repository<Car, UUID> {
Collection<CarSummary> findByCarYearGreaterThan(LocalDateTime now);
Collection<Car> findByAccidentYearIsNull();
}
I'm developing a Spring Boot application with Spring Data JPA. I'm using a custom JPQL query to group by some field and get the count. Following is my repository method.
#Query("SELECT v.status.name, count(v) as cnt FROM Pet v GROUP BY v.status.name")
List<Object[]> countByStatus();
It's working and result is obtained as follows:
[
[
"pending",
1
],
[
"available",
4
]
]
However, I would like my Rest endpoint to respond with an output which is formatted like this
{
"pending": 1,
"available": 4
}
How can I achieve this?
Basically you want to produce a JSON where its properties ("pending", "available") are dynamic and come from the SELECT v.status.name part of the query.
Create a DTO to hold the row values:
package com.example.demo;
public class ResultDTO {
private final String key;
private final Long value;
public ResultDTO(String key, Long value) {
this.key = key;
this.value = value;
}
public String getKey() {
return key;
}
public Long getValue() {
return value;
}
}
Change your query to create a new ResultDTO per row:
#Query("SELECT new com.example.demo.ResultDTO(v.status.name, count(v)) as cnt FROM Pet v GROUP BY v.status.name")
List<ResultDTO> countByStatus();
"com.example.demo" is my package, you should change it to yours.
Then from your service class or from your controller you have to convert the List<ResultDTO> to a Map<String, Long> holding all rows' keys and values.
final List<ResultDTO> repositoryResults = yourRepository.countByStatus();
final Map<String, Long> results = repositoryResults.stream().collect(Collectors.toMap(ResultDTO::getKey, ResultDTO::getValue));
Your controller should be able to transform final Map<String, Long> results to the desired JSON
I have a table
CatID | CategoryName | scatID | subCategoryName
2 User 1 x
2 User 2 y
2 User 3 z
2 User 4 a
2 User 5 b
I am able to get all the value in JSON formate using SpringBoot.
My Requirement :
I want to get the unique CategoryName attribute but in current scenario I am getting all User coming 5 times.
I am looking for solution. Please any one can help to get over using Spring Boot JPA implementation.
You can use the Query annotation in your repository interface.
For example, below snippet code return all distinct categoryName.
Declare a simple bean class:
package com.example.test;
public class CategoryNameClass {
private String CategoryName;
public CategoryNameClass(String CategoryName) {
this.CategoryName = CategoryName;
}
public String getCategoryName() {
return CategoryName;
}
public void setCategoryName(String categoryName) {
CategoryName = categoryName;
}
}
Then use the below query:
public interface ARepo extends JpaRepository<A, String> {
#Query("SELECT DISTINCT new com.example.test.CategoryNameClass(a.categoryName) FROM A a ")
List<CategoryNameClass> findAllCategoryName();
}
I am using simple Entity with 2 cols only. In my table PK col is varchar in db but in actual values stored is numerical in that col and other col is int. DB is MS SQL Server. And this table has 165 million records.
Table structure:
SECURITY_TAB
varchar(30) SECID PK;
int VERSION;
Entity
#Entity
#Table(name = "SECURITY_TAB")
public class Security {
#Id
#Column
private String secid;
#Column
private int version;
//... getter n setter n toString
}
Repository
public interface SecurityRepository extends JpaRepository<Security, String> {
#Query("SELECT s from Security s where secid= :secid")
Security findSecurityBySecid(#Param("secid") String secid)); //this is slow
//below is fine.
//#Query("SELECT s from Security s where secid='1111'")
//Security findSecurityBySecid();
}
TestClass
#RunWith(SpringRunner.class)
#SpringBootTest
public class SecurityTests {
#Autowired
private SecurityRepository securityRepository;
#Test
public void testSecurityBySecid() {
Instant start = Instant.now();
Security security = securityRepository.findSecurityBySecid("1111");
System.out.println(Duration.between(start, Instant.now()));
System.out.println(security);
System.out.println(Duration.between(start, Instant.now()));
}
}
This simple query is taking more than 20 secs,
While when I run similar query MS SQL Server Mgmt Studio or hard code the value in the query result is returned in mill seconds. So what is going wrong?
was able to solve:
The solution was to setup this property in the jdbc url : sendStringParametersAsUnicode=false
Full example if you are using MS SQL official driver : jdbc:sqlserver://yourserver;instanceName=yourInstance;databaseName=yourDBName;sendStringParametersAsUnicode=false;
Solution: sql server query running slow from java
I'm having spring data jpa repository.I the entity contain primary key id int and ipaddress string. The table contain only 1 record at a time otherwise null.
How do i retrieve the record using JPA , if it is not found return null.
#Repository
public interface IpConfigRepository extends JpaRepository<IpConfig, Integer> {
//
IpConfig findIpConfig();
}
According to the naming convention, you should define the method with the name findById(Integer id) ( assume the Id is the primary key )
Suppose you have a class A as shown below
class A{
private int id;
private String data;
// getters and setters
}
You can now search the items by the following ways.
public interface ARepo extends JpaRepository<A,Integer>{
// get all the records from table.
List<A> findAll();
// find record by id
A findById(int id);
// find record by data
A findByData(String data);
// find by date created or updated
A findByDateCreated(Date date);
// custom query method to select only one record from table
#Query("SELECT * FROM a limit 1;")
A findRecord();
}