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In all these tests I am using some strategies to make sure that tables and fields name generated by Hibernate will be the same as Eclipse-Link.

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Control Loop runtime uses persistence.xml file: is the deployment descriptor file for persistence using JPA. It specifies the persistence units and declares the managed persistence classes, the object/relation mapping, and the database connection details.

Hibernate

SpringBoot auto-configuration can automatically scan entity classes. In Control Loop Runtime we can use @EntityScan annotation because entity classes are not placed in the main application package or its sub-packages. In this situation, we need declare the package or list of packages in the main configuration class within @EntityScan annotation.

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Using these tables I have got this error: Cannot add or update a child row: a foreign key constraint fails (`controlloop`.`ExampleObjMap_Example`, CONSTRAINT `FK_ExampleObjMap_Example_name` FOREIGN KEY (`name`, `version`) REFERENCES `ExampleObjMap` (`name`, `version`))
Error Code: 1452

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Map of Objects using OneToMany (fixed)

Code Block
languagejava
titleJpaExampleObjMap
@Entity
@Table(name = "ExampleObjMap")
@Data
@EqualsAndHashCode
public class JpaExampleObjMap implements Serializable {

    private static final long serialVersionUID = 1L;

    @EmbeddedId
    @VerifyKey
    @NotNull
    private ExampleKey key;

    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
    @JoinTable(
            joinColumns = {@JoinColumn(name = "parent_name", referencedColumnName = "name"),
                    @JoinColumn(name = "parent_version", referencedColumnName = "version")},
            inverseJoinColumns = {@JoinColumn(name = "child_name", referencedColumnName = "name"),
                    @JoinColumn(name = "child_version", referencedColumnName = "version")})
    private Map<@NotNull String, @NotNull JpaExample> examples;
}

Eclipse-Link

MariaDB [controlloop]> SHOW CREATE TABLE ExampleObjMap_Example;
+-----------------------+-------------------------------------------------------------------------------------------------------------+
| Table                 | Create Table                                                                                                |
+-----------------------+-------------------------------------------------------------------------------------------------------------+
| ExampleObjMap_Example | CREATE TABLE `ExampleObjMap_Example` (
`parent_name` varchar(120) NOT NULL,
  `parent_version` varchar(20) NOT NULL,
  `child_name` varchar(120) NOT NULL,
  `child_version` varchar(20) NOT NULL,
  `EXAMPLES_KEY` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`parent_name`,`parent_version`,`child_name`,`child_version`),
  KEY `FK_ExampleObjMap_Example_child_name` (`child_name`,`child_version`),
  CONSTRAINT `FK_ExampleObjMap_Example_child_name` FOREIGN KEY (`child_name`, `child_version`)
REFERENCES `Example` (`name`, `version`),
  CONSTRAINT `FK_ExampleObjMap_Example_parent_name` FOREIGN KEY (`parent_name`, `parent_version`)
REFERENCES `ExampleObjMap` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------+-------------------------------------------------------------------------------------------------------------+


After saving the example:


MariaDB [controlloop]> select * from ExampleObjMap;
+---------------+---------+
| name          | version |
+---------------+---------+
| ExampleObjMap | 1.0.0   |
+---------------+---------+
MariaDB [controlloop]> select * from Example;
+--------+-----------+----------+---------+
| PRIMED | timeStamp | name     | version |
+--------+-----------+----------+---------+
|   NULL | NULL      | example1 | 1.0.0   |
|   NULL | NULL      | example2 | 1.0.0   |
+--------+-----------+----------+---------+
MariaDB [controlloop]> select * from ExampleObjMap_Example;
+---------------+----------------+------------+---------------+--------------+
| parent_name   | parent_version | child_name | child_version | EXAMPLES_KEY |
+---------------+----------------+------------+---------------+--------------+
| ExampleObjMap | 1.0.0          | example1   | 1.0.0         | MyKey1       |
| ExampleObjMap | 1.0.0          | example2   | 1.0.0         | MyKey2       |
+---------------+----------------+------------+---------------+--------------+


Map of Objects using ElementCollection

Code Block
languagejava
titleJpaExampleObjMap
@Entity
@Table(name = "ExampleObjMapEc")
@Data
@EqualsAndHashCode
public class JpaExampleObjMapEc implements Serializable {

    private static final long serialVersionUID = 1L;

    @EmbeddedId
    @VerifyKey
    @NotNull
    private ExampleKey key;

    @ElementCollection
    @Lob
    private Map<@NotNull String, @NotNull JpaExample> examples;
}

Eclipse-Link

MariaDB [controlloop]> describe ExampleObjMapEc;
+---------+--------------+------+-----+---------+-------+
| Field   | Type         | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name    | varchar(120) | NO   | PRI | NULL    |       |
| version | varchar(20)  | NO   | PRI | NULL    |       |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjMapEc_EXAMPLES;
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| Table                       | Create Table                                                                                                                                                                                                                                                                                                                                                                                                                                       |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| JpaExampleObjMapEc_EXAMPLES | CREATE TABLE `JpaExampleObjMapEc_EXAMPLES` (
`name` varchar(120) DEFAULT NULL,
  `version` varchar(20) DEFAULT NULL,
  `EXAMPLES` longblob DEFAULT NULL,
  `EXAMPLES_KEY` varchar(255) DEFAULT NULL,
  KEY `FK_JpaExampleObjMapEc_EXAMPLES_name` (`name`,`version`),
  CONSTRAINT `FK_JpaExampleObjMapEc_EXAMPLES_name` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjMapEc` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------------+-------------------------------------------------------------------------------------------------------+


Hibernate