Spring Boot JPA #UpdateTimestamp not working with Postgresql - postgresql

Question

I'm facing strange issue last modified date is not getting updated automatically.
I'm using Postgresql Version 12.3 and Springboot 2.2.4.RELEASE
Here's my Entity Class
#Entity
#Table(name = "users")
#org.hibernate.annotations.Entity(
dynamicUpdate = true
)
#Data
public class Users {
#Id
#GeneratedValue(generator = "UUID")
#GenericGenerator(
name = "UUID",
strategy = "org.hibernate.id.UUIDGenerator"
)
#Column(updatable = false, nullable = false)
private String userId;
private String userName;
private String userEmail;
private String userPhoneNumber;
#CreationTimestamp
#Column(updatable = false)
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+05:30")
private Timestamp createdOn;
#UpdateTimestamp
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+05:30")
private Timestamp lastUpdatedOn;
}
Database Records:
createdon | lastupdatedon
2020-08-27 07:43:37.994 | 2020-08-27 07:43:37.994
2020-08-07 07:49:22.797 | 2020-08-07 07:49:22.797
2020-08-12 13:38:43.503 | 2020-08-12 13:38:43.503
You can see both createdOn and lastUpdatedOn are same. Even though the records updated frequently last modified date is not getting updated.
I'm saving record with jpa repository
ex:
usersRepository.save(user);

Answer 1

Can you try using PrePersist & PreUpdate annotation instead of CreationTimestamp & UpdateTimestampas to have more control on the entity and apply below-
#Entity
#Table(name = "users")
#org.hibernate.annotations.Entity(
dynamicUpdate = true
)
#Data
public class Users {
#Id
#GeneratedValue(generator = "UUID")
#GenericGenerator(
name = "UUID",
strategy = "org.hibernate.id.UUIDGenerator"
)
#Column(updatable = false, nullable = false)
private String userId;
private String userName;
private String userEmail;
private String userPhoneNumber;
#Column(updatable = false)
private Timestamp createdOn;
#Column
private Timestamp lastUpdatedOn;
#PrePersist
public void onInsert() {
createdOn = Timestamp.from(ZonedDateTime.now(ZoneId.of("Asia/Kolkata")).toInstant());
lastUpdatedOn = createdOn;
}
#PreUpdate
public void onUpdate() {
lastUpdatedOn = Timestamp.from(ZonedDateTime.now(ZoneId.of("Asia/Kolkata")).toInstant());
}
}

Answer 2

Are you calling the save method within a transaction, by chance?
The timestamps are populated when written to the DB, so you won't see their values until after the transaction has been committed.
When I ran into this issue, I had code that looked like this:
#Transactional
public Response createFooBusinessLogic(Foo foo) {
var createdEntity = fooRepository.save(foo);
return someMethodUsingCreatedTime(createdEntity);
}
There are two solutions:
If the dates are required by another entity in the DB transaction, you can use saveAndFlush instead of save. This forces a write to the DB, returning back your created and modified dates.
Otherwise, refactor the save call into another method and annotate that method with #Transactional.
I went with option (2), which looked like this:
public Response createFooBusinessLogic(Foo foo) {
var createdEntity = facade.saveFoo(foo);
return someMethodUsingCreatedTime(createdEntity);
}
// In Facade.java
#Transactional
public Foo saveFoo(Foo foo) {
return fooRepository.save(foo);
}
Note that for the transaction annotation to work, the call must not be self-invoking (ie. must be called on another class) and the method must be public.