Spring boot/Hibernate fails creating table - mysql

Question

I am getting this warn when I try to start my spring boot application:
2018-09-30 07:34:23.097 INFO 59360 --- [ main] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.MySQL5Dialect
Hibernate: create table social_link (author_username varchar(255) not null, type varchar(255) not null, value varchar(255), primary key (author_username, type)) engine=MyISAM
2018-09-30 07:34:24.067 WARN 59360 --- [ main] o.h.t.s.i.ExceptionHandlerLoggedImpl : GenerationTarget encountered exception accepting command : Error executing DDL via JDBC Statement
Strange thing is that I can execute SQL statement via the SQL workbench without a problem and everything works fine after that.
Here is the entity that is responsible for that table:
#Entity
public class SocialLink {
#EmbeddedId
private SocialLinkKeyEmbeddable id = new SocialLinkKeyEmbeddable();
private String value;
#ManyToOne
#MapsId("author_username")
#JoinColumns({
#JoinColumn(name="author_username", referencedColumnName="author_username")
})
private Author author;
//Getters and setters
}
#Embeddable
public class SocialLinkKeyEmbeddable implements Serializable {
#Column(name = "author_username")
private String author_username;
private String type;
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getAuthor_username() {
return author_username;
}
public void setAuthor_username(String author_username) {
this.author_username = author_username;
}
#Override
public int hashCode() {
return super.hashCode();
}
#Override
public boolean equals(Object obj) {
return super.equals(obj);
}
}
public interface SocialLinkRepository extends CrudRepository<SocialLink, SocialLinkKeyEmbeddable> {
}

Answer 1

The problem was with the length of the key. MySQL was pretending it is larger than 1000 bytes. It seems its a common problem with MyISAM storage engine.
In order to fix it I added:
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL55Dialect
to my applicaiton.properties and now the problem is fixed.
Was using this post as reference
#1071 - Specified key was too long; max key length is 1000 bytes

Answer 2

I had a similar problem caused by spring.jpa.database-platform property set to MySQL5Dialect.
Setting the property to MySQL8Dialect or removing it altogether (which enables auto-configuration) solved the problem.

Answer 3

I added a column length to my ID field to prevent the varchar(255) default.
#Entity
public class MyEntity {
#Id
#Column(length = 64)
private String id;
...
}

Answer 4

For those who are only using Hibernate (not Spring), edit the SQL dialect property from hibernate.cfg.xml file, located in src/main/resources folder.
<property name="dialect">org.hibernate.dialect.MySQL55Dialect</property>
Or remove the dialect property altogether.

Answer 5

Error-Caused by: java.sql.SQLSyntaxErrorException: Specified key was too long; max key length is 1000 bytes
operation perform- #Id private String userName;
Solution
step1-Go to mysql database--> step2-Go to schema setting -->step3-change Default charset to latin1--> step 4-Run on server your spring mvc program--> step 5- Finally Your table is created with #Id on String

Answer 6

I had the same issue. I resolved it by assigning char set to my database on creation:
CREATE DATABASE mydb DEFAULT CHARACTER SET utf8mb3;