How can solve JSON column in H2

Question

I use in application MySQL 5.7 and I have JSON columns. When I try running my integration tests don\'t work because the H2 database can\'t create the table. This is the erro

Answer 1

My problem was with JSONB since H2 does not support it as was already mentioned.

One more problem is that when you insert a json, H2 transforms it into a json object string which makes jackson serialization fail. ex: "{\"key\": 3}" instead of {"key": 3} . One solution is to use FORMAT JSON when inserting the json, but then you need to have duplicate insert files if you are using flyway, for example.

Inspired by the @madz answer I came across with this solution:

Create a custom JsonbType (on production - e.g. main/java/com/app/types/JsonbType.java)

import com.vladmihalcea.hibernate.type.json.JsonBinaryType;

public class JsonbType extends JsonBinaryType {
  private static final long serialVersionUID = 1L;
}

Create a custom JsonbType (on tests - e.g. test/java/com/app/types/JsonbType.java)

import com.vladmihalcea.hibernate.type.json.JsonStringType;

public class JsonbType extends JsonStringType {
  private static final long serialVersionUID = 1L;
  @Override
  public String getName() {
      return "jsonb";
  }
}

Create an alias type from JSONB to JSON only on tests (h2):

-- only on H2 database
CREATE TYPE "JSONB" AS TEXT;

note: I'm using flyway which make it easy to do but you can follow @jchrbrt suggestion

Finally you declare the type on your entity model, as follows:

import com.app.types.JsonbType;

@TypeDef(name = "jsonb", typeClass = JsonbType.class)
@Entity(name = "Translation")
@Table(name = "Translation")
@Data
public class Translation {
  @Type(type = "jsonb")
  @Column(name="translations")
     private MySerializableCustomType translations; 
  }
}

That's it. I hope it helps someone.