[FIXED] Java @Id without @column(nullable=false)

Issue

Am i right that @Id annotation add two constraints in database:

• nullable=false
• unique=true

? I saw a lot of examples in the Internet with syntax like

@Id
@Column(name="xxx",nullable=false)
BigInteger id

It is correct? Do i really need this nullable=false?

Solution

Yes you are right. If you use hibernate schema generation mechanism, all @Id columns in the database will be NOT NULL and have unique index by default.

In the other hand, @Column(nullable=false) declaration is absolutely meaningless if you create the schema any other way.

Answered By - Alex Bondarev