How to add enum field in postgres?

Question

In my model there is an enum field, trying to add an enum field to the database, but does not work, can you comment?

public class ChatMessage {
private MessageType messageType;
private String content;
private String sender;
public enum MessageType {
 CHAT,
 JOIN,
 LEAVE
}

my postgre code

CREATE TYPE messageType AS ENUM ('CHAT', 'JOIN', 'LEAVE');
CREATE TABLE "chatMessage" (
id SERIAL UNIQUE PRIMARY KEY,
messageType messageType,
content VARCHAR(255) NOT NULL,
sender VARCHAR(255) NOT NULL
);

I suppose that I incorrectly declare the variable enum in postgres

Answer 1

Use Enumerated Annotation and Spring will handle this for you. But in general Enums will be VARCHAR(X) in Postgres (see second link)

public class ChatMessage {
 @Enumerated(EnumType.STRING)
 private MessageType messageType;
 private String content;
 private String sender;
}

http://tomee.apache.org/examples-trunk/jpa-enumerated/

https://vladmihalcea.com/the-best-way-to-map-an-enum-type-with-jpa-and-hibernate/

• Самир Шахмурадлы: CREATE TYPE messageType AS ENUM ('CHAT', 'JOIN', 'LEAVE'); do not use?
• DCO: You can try this. But you need to check if Spring JPA is fine with this. It is possible that @Enumerated(EnumType.STRING) is also triggering creating an enum type. I would jpa create your database.
• DCO: If your Enum will be extended in your Java Entity it could be necessary to edit your postgres enum type as well. Let JPA manage it...

Answer 2

If I get it right, according to the documentation your doing fine.

Although in their example they choose a different name for the column that references the Enum Type. Try change it, like, messages messageType.

Another example: https://tapoueh.org/blog/2018/05/postgresql-data-types-enum/#postgresql-enum-data-type