Spring Data Jpa, select based on two column values - sql

Question

Good Morning,
I have the following table:
_____________________
Name Status Num
A Good 6
B Bad 6
C Bad 7
I want to select all rows where "Status = 'Good' AND Num = '6'" OR "Status = 'Bad' AND Num = '7'"
So I would select rows with Names A and C from the above reference data.
I am hoping to be able to pass in two equal sized lists (ordered in the way I desire the query to be constructed), but have been unable to figure this out. The standard queries (SelectXByStatusAndNum) query generates SQL using 'IN' statements, and returns all 3 rows in the above data instead of just two.
Any insight appreciated

Answer 1

I believe the best way is to use a #Query annotation in the repository:
#Entity
#Table(name = "table_name")
public class TableName {
#Id
#Basic(optional = false)
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "ID")
private Long id;
#Column(name = "name")
private String name;
#Column(name = "status")
private String status;
#Column(name = "num")
private Integer num;
/**
* getters/setters, etc
**/
public interface TableNameRepository extends CrudRepository<TableName, Long> {
#Query("select t from TableName t where (status = :status1 and num = :num1 or status = :status2 and num = :num2)")
List<TableName> findByStatusAndNumOrStatusAndNum(#Param("status1") String status1,
#Param("num1") Integer num1, #Param("status2") String status2, #Param("num2") Integer num2);
}
It's a way to get values for a given parameters. In case of collections as parameters there is no in-box case due to RDBMS concept. You just can write some java code based on the key-valued parameter and collect results:
public interface TableNameRepository extends CrudRepository<TableName, Long> {
List<TableName> findByStatusAndNumIn(String status, Collection<Integer> nums);
}
List<TableName> result = new ArrayList<>();
List<TableName> itemGood = findByStatusAndNumIn("Good", numsGood);
List<TableName> itemBad = findByStatusAndNumIn("Bad", numsBad);
result.addAll(itemGood);
result.addAll(itemBad);

Answer 2

Instead of equal size lists, I suggest creating an object with both status and num and provide a list of those - I called it CustomCriteria below. Since there is no straightforward way to handle this with standard spring data query methods I believe the best way is to do this with criteria builder in a custom repository that builds the list of OR's from a list of AND predicates based on the criteria entries in the provided list. For example:
public List<YourTable> findMatching(List<CustomCriteria> customCriteriaList) {
CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<YourTable> criteriaQuery = criteriaBuilder.createQuery(YourTable.class);
Root<YourTable> itemRoot = criteriaQuery.from(YourTable.class);
List<Predicate> predicates = new ArrayList<>(customCriteriaList.size());
for (CustomCriteria customCriteria : customCriteriaList) {
Predicate predicateForNum
= criteriaBuilder.equal(itemRoot.get("num"), customCriteria.getNum());
Predicate predicateForStatus
= criteriaBuilder.equal(itemRoot.get("status"), customCriteria.getStatus());
predicates.add(criteriaBuilder.and(predicateForNum, predicateForStatus));
}
Predicate finalPredicate = criteriaBuilder.or(predicates.toArray(new Predicate[predicates.size()]));
criteriaQuery.where(finalPredicate);
return entityManager.createQuery(criteriaQuery).getResultList();
}