Unique Key Constraint in Spring Data Jpa - spring-boot

Question

How to make a field unique in pojo using spring data jpa?I know how to do that using jpa
For reference: multi column constraint with jpa
If there is a way, is it possible to use with spring boot?

Answer 1

Use the #UniqueConstraint annotation to specify that a unique constraint is to be included in the generated DDL for a primary or secondary table.
Alternately, to ensure a field value is unique you can write
#Column(unique=true)
String myField;

Answer 2

With Spring Data JPA you are using JPA, so you specify the unique constraint using JPA. Nothing special from Spring Boot or Spring Data on that front.

Answer 3

Um exemplo em Kotlin:
Entity
#Table(name = "TBL_XXX",
uniqueConstraints = [
UniqueConstraint(name = "sessionid_uindex", columnNames = ["sessionId"])
]
)
data class XxxReturn(
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "XXX_ID")
var id: Long? = null,
var sessionId: String,
var msg: String
)

Answer 4

If you have a single column in the table that has UNIQUE KEY constraint then you can simply add the attribute unique=true in the annotation #Column
CODE SNIPPET:
#Column(name = "unique_key_field", nullable = false, unique = true)
String uniqueKeyFied;
In case if you have multiple Unique key constraints in the table then you have to simply follow with the JPA annotations as the spring-boot-data-starter does not provide any special annotations for the table constraints(KEY/UNIQUEKEY).
CODE SNIPPET:
#Entity
#Table(name = "table_name", uniqueConstraints={
#UniqueConstraint( name = "idx_col1_col2", columnNames ={"col1","col2"})
})