I have table/entity which has varchar(255) field that can store values of multiple data types and type field which indicates what kind of value type it is. I want to perform join only if data type is of certain value ie. document.
Example:
#Entity
#Table(name = "ACT_HI_DETAIL")
public class TaskDetailsVariable implements Serializable {
#Id
#Column(name = "ID_")
private String id;
#Column(name = "TEXT_")
private String value;
#Column(name = "VAR_TYPE_")
private String type;
#ManyToOne
#JoinColumn(name = "TEXT_")
#WhereJoinTable(clause = "VAR_TYPE_ = 'document'") // this doesn't work
private Document document; // this should be joined only if type is document
}
When I try the example above, I get the error because it tries to join all LONG_ values. I have also tried #JoinFormula and #Where.
Related
The user can search for products if any product shown in the result exists in the user_favorites table so the show flag tells the front-end this product was added for this user by user_id and product_id. with spring boot and spring data.
My Entity :
#Id
#Column(name = "catId")
private Integer catId;
#Column(name = "cat_no")
private String catNo;
#Column(name = "cat_sn")
private String catSn;
#Column(name = "doc_ref")
private String docRef;
#Column(name = "user_id")
private Integer userId;
#Column(name = "updated_at")
private String updatedAt;
#Column(name = "created_at")
private String createdAt;
I tried that using #Formula but nothing happing always returns null. and if it's done by #Formula how can i add parameters to #Formula
#Formula(value = "SELECT count(*) as checker FROM fb_user_favorites WHERE cat_id = 34699 AND user_id = '52') ")
#Transient
private String checker;
#Transient is part of JPA spec. In Hibernate fields marked with this annotation just simply ignored/excluded from any JPA engine/runtime logic.
#Formula is part of Hibernate. Fields, marked with it, don't persisted by Hibernate (first argument do not use #Transient as redundant), values are calculated by provided SQL when executing query for entity.
So for Hibernate to see this fields, they should not be excluded by #Transient
TL;DR remove #Transient annotation
Complicated but fast working way.
Adding isFavorite field to the entity:
#Transient
private boolean isFavorite;
Create an entity linking Product and User:
public class ProductFavorite {
#Id
#GeneratedValue(strategy = IDENTITY)
private Long id;
#ManyToOne(optional = false, fetch = LAZY)
private Product product;
#ManyToOne(optional = false, fetch = LAZY)
private User user;
}
Then create a repository with a method to find the user's favorite products:
#Repository
public interface ProductLikeRepository extends JpaRepository<ProductFavorite, Long> {
#Query("select f.product.id from ProductFavorite f where f.product in ?1 and f.user = ?2")
Set<Integer> findProductIdsByIdsAndUser(List<Product> products, User user);
}
And at the end, write a method that will fill in the isFavorite field:
public void fillFavorite(List<Product> products, User user) {
if (products.isEmpty()) {
return;
}
var likedIds = favoriteRepository.findProductIdsByIdsAndUser(products, user);
for (Product product : products) {
product.setFavorite(likedIds.contains(product.getId()));
}
}
You need to call it manually:
List<Product> products = productRepository.findAll();
fillFavorite(products, currentUser());
I want to join column without object reference. is that possible?
I want to do foreign key without object reference like that
#Data
#Entity
#Table(name = "HRM_EMPLOYEE_SALARY_INCREMENT")
public class EmployeeSalaryIncrement implements Serializable {
private static final long serialVersionUID = 9132875688068247271L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="ID")
private Integer id;
#Column(name = "REFERENCE_NO")
private String referenceNo;
#ManyToOne
#JoinColumn(name = "AUTHORITY", referencedColumnName = "id")
private Integer authority;
#ManyToOne
#JoinColumn(name = "PART_TWO_REGISTER_ID")
private Integer partTwoRegisterId;
#Column(name = "PART_TWO_ORDER_NO")
private String partTwoOrderNo;
#Column(name = "REMARKS")
private String remarks;
#Column(name = "HRM_TYPE")
private Integer hrmType;
}
If I found solve this problem, it will helpful for me.
Joining is not needed in this case. If you only need the foreign key value, then simply add the column as a #Column like any other:
#Data
#Entity
#Table(name = "HRM_EMPLOYEE_SALARY_INCREMENT")
public class EmployeeSalaryIncrement implements Serializable {
private static final long serialVersionUID = 9132875688068247271L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="ID")
private Integer id;
#Column(name = "AUTHORITY")
private Integer authority;
// other fields
// ...
}
No, I don't think that you can join columns between two entities without adding the reference of one to the related entity. You will have to create one entity class corresponding to each of your relational database table and add the reference of one to the other to establish relation.
However, I understand that you may not need all the attributes from your related table based upon your use case, and only wish to select one column from it. You can do that either by only adding required attributes in your joined table entity class (if you are sure you won't need other attributes for that table anywhere else).
Or you can use custom queries using JPQL in your repository class which selects only the required attributes from the tables that you have joined.
I will show you an example of the second way:
//Say, this is your entity class where you wish to join other table to fetch only one attribute from the joined table-
#Entity
#Table(name = "TABLE1", schema = "SCHEMA1")
public class Table1 {
#Id
#Column(name = "ID")
private String id;
#Column(name = "TABLE2_COLUMN")
private String table2Column;
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "TABLE2_COLUMN1")
private Table2 table2; //refrence of the joined table entity object
}
// And this is the joined table entity class
#Entity
#Table(name = "TABLE2", schema = "SCHEMA1")
public class Table2 {
#Id
#Column(name = "ID")
private String id;
#Column(name = "TABLE2_COLUMN1")
private String table2Column1;
#Column(name = "TABLE2_COLUMN2")
private String table2Column2; // The column which we want to select from the joined table
}
In your repository class -
#Repository
public interface Table1Repository extends JpaRepository<Table1, String> {
#Query("SELECT t1 FROM Table1 t1 WHERE t1.id = :id")
public List<Table1> getTable1Rows(#Param("id") String id);
#Query("SELECT t1.table2.table2Column2 FROM Table1 t1 WHERE t1.id = :id")
public String getTable2Column2(#Param("id") String id);
}
Based upon the response from Markus Pscheidt below, I agree when he said there's no need to join the entities if you only need the attribute which is a foreign key. As foreign key is already present as an attribute in your entity (or table) you are working with.
If you need to fetch any other column apart from foreign key, then you may use JPQL to fetch the exact column that you wish to select.
Hi I have couple of Entity classes as below, using lombok for getter and setters
Parent Entity Class have
#Table(name = "PARTY")
#Entity
public class Party {
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#OneToMany(targetEntity = DVLoanParticipants.class,cascade = CascadeType.ALL)
#JoinColumn(name = "PARTY_ID")
#MapKey(name="dvpParticipantName")
#LazyCollection(LazyCollectionOption.FALSE)
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
}
Child Entity Class have
#Table(name = "DV_LOAN_PARTICIPANTS")
#Entity
public class DVLoanParticipants implements Serializable {
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#Id
#Column(name = "DVP_PARTICIPANT_NAME")
private String dvpParticipantName;
#Column(name = "DVP_PARTICIPANT_TYPE")
private String dvpParticipantType;
}
In service class i am calling save operation as
repository.save(parentEntityObject);
I am able to execute update statements ,but when i try to insert new row for child entity class i am getting an error saying
cannot insert NULL into ("ABC"."DV_LOAN_PARTICIPANTS"."PARTY_ID")
But if i print the parentEntityObject just before the save operation i see the values like
(partyId=12345678, dvpParticipantName=XYZ, dvpParticipantType=VKP)
I see the query formed as
insert
into
DV_LOAN_PARTICIPANTS
(DVP_PARTICIPANT_TYPE, PARTY_ID, DVP_PARTICIPANT_NAME)
values
(?, ?, ?)
Just before te save i am seeing valules in the Object
Builder=DVLoanParticipants(partyId=123456, dvpParticipantName=Builder,
dvpParticipantType=Individual)
Update
This is the setting part for values
DVLoanParticipants dvLoanParticipants = new
DVLoanParticipants();
dvLoanParticipants.setPartyId(Long.valueOf(partyId));
dvLoanParticipants.setDvpParticipantName("Builder");
dvLoanParticipants.setDvpParticipantType("Individual");
Party party = new Party();
Map<String, DVLoanParticipants> dvLoanParticipantsMap = new
java.util.HashMap<>();
dvLoanParticipantsMap.put("Builder", dvLoanParticipants);
party.setPartyId(Long.valueOf(partyId));
party.setDvLoanParticipantsMap(dvLoanParticipantsMap);
repository.save(party);
What is the mistake i am doing ?
The root cause of your problem in this part:
#OneToMany(targetEntity = DVLoanParticipants.class,cascade = CascadeType.ALL)
#JoinColumn(name = "LOAN_ID")
#MapKey(name="dvpParticipantName")
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
actually for your case the column name in the #JoinColumn means:
If the join is for a unidirectional OneToMany mapping using a foreign key mapping strategy, the foreign key is in the table of the target entity.
So, assuming for the clarity that you want to map the following schema:
create table PARTY
(
PARTY_ID int,
-- ...
primary key (PARTY_ID)
);
create table DV_LOAN_PARTICIPANTS
(
PARTY_ID int,
DVP_PARTICIPANT_NAME varchar(50),
DVP_PARTICIPANT_TYPE varchar(10),
-- ...
primary key (PARTY_ID, DVP_PARTICIPANT_NAME),
foreign key (PARTY_ID) references PARTY(PARTY_ID)
);
You can use the following mapping:
#Entity
#Table(name = "PARTY")
public class Party
{
#Id
#Column(name = "PARTY_ID")
private Long partyId;
// I use fetch = FetchType.EAGER instead of deprecated #LazyCollection(LazyCollectionOption.FALSE)
// targetEntity = DVLoanParticipants.class is redundant here
#OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
#JoinColumn(name = "PARTY_ID") // this is DV_LOAN_PARTICIPANTS.PARTY_ID column
#MapKey(name = "dvpParticipantName")
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
public Party()
{
dvLoanParticipantsMap = new HashMap<>();
}
// getters / setters
public void addParticipant(DVLoanParticipants p)
{
this.dvLoanParticipantsMap.put(p.getDvpParticipantName(), p);
p.setPartyId(getPartyId());
}
}
#Entity
#Table(name = "DV_LOAN_PARTICIPANTS")
public class DVLoanParticipants implements Serializable
{
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#Id
#Column(name = "DVP_PARTICIPANT_NAME")
private String dvpParticipantName;
#Column(name = "DVP_PARTICIPANT_TYPE")
private String dvpParticipantType;
// getters / setters
}
and example how to save:
Party party = new Party();
party.setPartyId(2L);
// ...
DVLoanParticipants part1 = new DVLoanParticipants();
part1.setDvpParticipantName("Name 3");
part1.setDvpParticipantType("T1");
DVLoanParticipants part2 = new DVLoanParticipants();
part2.setDvpParticipantName("Name 4");
part2.setDvpParticipantType("T1");
party.addParticipant(part1);
party.addParticipant(part2);
repository.save(party);
and several notes:
The LazyCollectionOption.TRUE and LazyCollectionOption.FALSE values are deprecated since you should be using the JPA FetchType attribute of the #OneToMany association.
You use hibernate specific approach for mapping сomposite identifiers. As it's mentioned in the hibernate documentation:
The restriction that a composite identifier has to be represented by a primary key class (e.g. #EmbeddedId or #IdClass) is only JPA-specific.
Hibernate does allow composite identifiers to be defined without a primary key class via multiple #Id attributes.
But if you want to achieve more portability you should prefer one of the jpa allowed approaches.
i have a spring application where i wish to find a unique record which matches mutiple column values supplied at once. How should i write my own custom method for it in an interface implementing CrudRepository
below is the model and the interface
#Entity
#Table(name = "tenant_subscriptions")
public class TenantSubscriptions {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "userId")
private Long userId;
#Column(name = "service_id")
private Long serviceId;
#Column(name = "feature_id")
private Long featureId;
#Column(name = "subfeature_id")
private Long subfeatureId;
#Column(name = "status")
private String Status;
#Column(name = "subscription_id")
private String SubscriptionId;
public interface TenantSubscriptionsRepository extends CrudRepository<TenantSubscriptions, Long> {
}
You don't need to write your own query if it's not something super complex.
For matching multiple column values in the same table you can use query from method name.
There is two way according to documentation and Query creation:
By deriving the query from the method name directly.
By using a manually defined query.
TenantSubscriptions findByUserIdAndServiceIdAndFeatureId(Long userId, Long serviceId, Long featureId); //Hibernate will recognize your DB object and this will work (no extra thing needs to be done)
Query:
#Query(value = "SELECT u FROM User u WHERE u.status = 'ACTIVE' AND u.creationDate <= current_date()")
List<User> findUserCandidates();
Inner join query:
#Query(value = "SELECT DISTINCT u FROM User u INNER JOIN UserAccount ua ON u.id = ua.userId WHERE ua.status = 'ACTIVE' AND ua.companyId = :companyId")
List<Bank> findBanksByCompany(Integer companyId);
You can find an entry by multiple attributes by chaining them in the interface method name. Also, Spring Data also inspects the return type of your method.
Example:
TenantSubscriptions findOneByServiceIdAndFeatureId(Long serviceId, Long featureId);
This will return the one entry that matches both attributes.
See also this answer and the Spring Data Reference Guide.
I want to set only fixed parameters from DTO. I have 3 Entity (tables) which are connected with FK or PK. So when I am getting data from database using ID of Table A. Jpa will give me All data with its child that's exactly I want.
public class AEntity{
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name = "a_id")
private Long aId;
private String name;
private String model;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "b_id")
private bEntity bentity;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "c_uid")
private cEntity centity;
#JoinColumn(name = "d_id")
#OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
private List<dEntity> d;
}
Like this I have B,C,D Entity also. now here I am getting Data by A_id. And created aDTO like:
public class aDTO {
private Long a_Id;
#JsonProperty(required=true)
private String name;
#JsonProperty(required=true)
private String model;
#Valid
private List<AllbDTO> bList;
private List<AllcDTO> cList;
}
And using this code:
{
Type targetListType = new TypeToken<List<aDTO>>() {
}.getType();
List<aDTO> aDTOs = mapper.map(AllDAtaByQuery, targetListType);
return aDTOs ;
}
now "AllDAtaByQuery" its an entity object to storedata from query and all are working fine. Its giving me list of a then inner list with b tables data and so on with all field.
Q: Is it possible that I tell mapper to map specific fields i want So i can send response with specific field?
Like b table have 6 fields but I want only 2 fields data in response by using same DTO. so i will use same dto for all other query and manipulate the response according need.