The goal of this document is to show implications for tosca model template to move from Eclipse-Link to Hibernate. Primary focus is to show the database compatibility and eventually schema changes where is necessary.
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.
Definitions
- ElementCollection: Specifies a collection of instances of a basic type or embeddable class. Must be specified if the collection is to be mapped by means of a collection table.
- OneToMany: Specifies a many-valued association with one-to-many multiplicity. If the collection is defined using generics to specify the element type, the associated target entity type need not be specified; otherwise the target entity class must be specified. If the relationship is bidirectional, the
mappedBy
element must be used to specify the relationship field or property of the entity that is the owner of the relationship. TheOneToMany
annotation may be used within an embeddable class contained within an entity class to specify a relationship to a collection of entities. If the relationship is bidirectional, themappedBy
element must be used to specify the relationship field or property of the entity that is the owner of the relationship. When the collection is ajava.util.Map
, thecascade
element and theorphanRemoval
element apply to the map value.
Persistence classes scanning
Eclipse-Link
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.
Implications using Hibernate and SpringBoot scan
persistence.xml
file doesn't contain all JPA classes in "org.onap.policy.models.tosca.simple.concepts" package, so SpringBoot will intercept additional classes (not defined into persistence.xml
file) and will generate additional tables into controlloop database for them: ToscaEventFilter, ToscaModel, ToscaServiceTemplates, ToscaServiceTemplates_ToscaServiceTemplate, ToscaTimeInterval, ToscaTrigger.
Schema generation
Boolean and TimeStamp
In the most of the cases, in tosca model template there is compatibility in field types. Only two types (java.util.Date and Boolean) are not compatible between Eclipse-Link and Hibernate.
Eclipse-Link
MariaDB [controlloop]> describe Example;
+-----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| PRIMED | tinyint(1) | YES | | 0 | |
| timeStamp | datetime(3) | YES | | NULL | |
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+-----------+--------------+------+-----+---------+-------+
Hibernate
MariaDB [controlloop]> describe Example;
+-----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
| primed | bit(1) | YES | | NULL | |
| timeStamp | datetime(6) | YES | | NULL | |
+-----------+--------------+------+-----+---------+-------+
Boolean and TimeStamp (fixed)
columnDefinition will override the sql DDL generated by hibernate for this particular column, but it is non portable.
Eclipse-Link
MariaDB [controlloop]> describe Example;
+-----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| PRIMED | tinyint(1) | YES | | NULL | |
| timeStamp | datetime(3) | YES | | NULL | |
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+-----------+--------------+------+-----+---------+-------+
Hibernate
MariaDB [controlloop]> describe Example;
+-----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
| primed | tinyint(1) | YES | | NULL | |
| timeStamp | datetime(3) | YES | | NULL | |
+-----------+--------------+------+-----+---------+-------+
Map and List of Strings
When @ElementCollection is used properly there is enough compatibility. We can see that in the scenario shown below: there is only a small difference in how the primary keys are build.
Eclipse-Link
MariaDB [controlloop]> describe ExampleCollection;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleCollection_ATTRIBUTES;
+---------------------------------+---------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------------------------------+---------------------------------------------------------------------------------------------------+
| JpaExampleCollection_ATTRIBUTES | CREATE TABLE `JpaExampleCollection_ATTRIBUTES` (
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) DEFAULT NULL,
`ATTRIBUTES` longtext DEFAULT NULL,
`ATTRIBUTES_KEY` varchar(255) DEFAULT NULL,
KEY `FK_JpaExampleCollection_ATTRIBUTES_name` (`name`,`version`),
CONSTRAINT `FK_JpaExampleCollection_ATTRIBUTES_name` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleCollection` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+---------------------------------+---------------------------------------------------------------------------------------------------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleCollection_OCCURRENCES;
+----------------------------------+--------------------------------------------------------------------------------------------------+
| Table | Create Table |
+----------------------------------+--------------------------------------------------------------------------------------------------+
| JpaExampleCollection_OCCURRENCES | CREATE TABLE `JpaExampleCollection_OCCURRENCES` (
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) DEFAULT NULL,
`OCCURRENCES` varchar(255) DEFAULT NULL,
KEY `FK_JpaExampleCollection_OCCURRENCES_name` (`name`,`version`),
CONSTRAINT `FK_JpaExampleCollection_OCCURRENCES_name`
FOREIGN KEY (`name`, `version`) REFERENCES `ExampleCollection` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+----------------------------------+--------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleCollection;
+-------------------+---------+
| name | version |
+-------------------+---------+
| ExampleCollection | 1.0.0 |
+-------------------+---------+
MariaDB [controlloop]> select * from JpaExampleCollection_ATTRIBUTES;
+-------------------+---------+-----------------+----------------+
| name | version | ATTRIBUTES | ATTRIBUTES_KEY |
+-------------------+---------+-----------------+----------------+
| ExampleCollection | 1.0.0 | ValueAttribute2 | Attribute2 |
| ExampleCollection | 1.0.0 | ValueAttribute1 | Attribute1 |
+-------------------+---------+-----------------+----------------+
MariaDB [controlloop]> select * from JpaExampleCollection_OCCURRENCES;
+-------------------+---------+-------------+
| name | version | OCCURRENCES |
+-------------------+---------+-------------+
| ExampleCollection | 1.0.0 | Occurrence1 |
| ExampleCollection | 1.0.0 | Occurrence2 |
+-------------------+---------+-------------+
Hibernate
MariaDB [controlloop]> describe ExampleCollection;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleCollection_ATTRIBUTES;
+---------------------------------+---------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------------------------------+---------------------------------------------------------------------------------------------------+
| JpaExampleCollection_ATTRIBUTES | CREATE TABLE `JpaExampleCollection_ATTRIBUTES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`attributes` longtext DEFAULT NULL,
`attributes_KEY` varchar(255) NOT NULL,
PRIMARY KEY (`name`,`version`,`attributes_KEY`),
CONSTRAINT `FKrapsbq2h8eev8wstn9x11mfnr` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleCollection` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+---------------------------------+---------------------------------------------------------------------------------------------------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleCollection_OCCURRENCES;
+----------------------------------+--------------------------------------------------------------------------------------------------+
| Table | Create Table |
+----------------------------------+--------------------------------------------------------------------------------------------------+
| JpaExampleCollection_OCCURRENCES | CREATE TABLE `JpaExampleCollection_OCCURRENCES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`occurrences` varchar(255) DEFAULT NULL,
KEY `FKbvv6rdypcejif8yy1kr43vpob` (`name`,`version`),
CONSTRAINT `FKbvv6rdypcejif8yy1kr43vpob` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleCollection` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+----------------------------------+--------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleCollection;
+-------------------+---------+
| name | version |
+-------------------+---------+
| ExampleCollection | 1.0.0 |
+-------------------+---------+
MariaDB [controlloop]> select * from JpaExampleCollection_ATTRIBUTES;
+-------------------+---------+-----------------+----------------+
| name | version | attributes | attributes_KEY |
+-------------------+---------+-----------------+----------------+
| ExampleCollection | 1.0.0 | ValueAttribute1 | Attribute1 |
| ExampleCollection | 1.0.0 | ValueAttribute2 | Attribute2 |
+-------------------+---------+-----------------+----------------+
MariaDB [controlloop]> select * from JpaExampleCollection_OCCURRENCES;
+-------------------+---------+-------------+
| name | version | occurrences |
+-------------------+---------+-------------+
| ExampleCollection | 1.0.0 | Occurrence1 |
| ExampleCollection | 1.0.0 | Occurrence2 |
+-------------------+---------+-------------+
JpaToscaCapabilityAssignment_ATTRIBUTES table
Currently in tosca model template, due the complexity of the schema there are some issues in foreign keys using Collections of String. The SQL code below shows the JpaToscaCapabilityAssignment_ATTRIBUTES table.
Eclipse-Link
MariaDB [controlloop]> SHOW CREATE TABLE JpaToscaCapabilityAssignment_ATTRIBUTES;
+-----------------------------------------+-------------------------------------------------------------------------------------------+
| Table | Create Table |
+-----------------------------------------+-------------------------------------------------------------------------------------------+
| JpaToscaCapabilityAssignment_ATTRIBUTES | CREATE TABLE `JpaToscaCapabilityAssignment_ATTRIBUTES` (
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) DEFAULT NULL,
`ATTRIBUTES` longtext DEFAULT NULL,
`ATTRIBUTES_KEY` varchar(255) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------------------------+-------------------------------------------------------------------------------------------+
I have not found out why foreign key has not be generated in this table and in all '_ATTRIBUTES', '_META' and '_CONSTRAINTS' tables as well.
Hibernate
MariaDB [controlloop]> SHOW CREATE TABLE JpaToscaCapabilityAssignment_ATTRIBUTES;
+-----------------------------------------+-------------------------------------------------------------------------------------------+
| Table | Create Table |
+-----------------------------------------+-------------------------------------------------------------------------------------------+
| JpaToscaCapabilityAssignment_ATTRIBUTES | CREATE TABLE `JpaToscaCapabilityAssignment_ATTRIBUTES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`attributes` longtext DEFAULT NULL,
`attributes_KEY` varchar(255) NOT NULL,
PRIMARY KEY (`name`,`version`,`attributes_KEY`),
CONSTRAINT `FKjuqj4nashp9jx76h5eh5psp7l` FOREIGN KEY (`name`, `version`)
REFERENCES `ToscaCapabilityAssignment` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------------------------+-------------------------------------------------------------------------------------------+
Map of Objects using ElementCollection
ElementCollection should be used with basic type or embeddable class, this example shows side effects using it with entity.
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 |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleObjMapEc;
+---------------+---------+
| name | version |
+---------------+---------+
| ExampleObjMap | 1.0.0 |
+---------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjMapEc_EXAMPLES;
+---------------+---------+---------------------------+--------------+
| name | version | EXAMPLES | EXAMPLES_KEY |
+---------------+---------+---------------------------+--------------+
| ExampleObjMap | 1.0.0 | .... <binary code> .... | MyKey1 |
| ExampleObjMap | 1.0.0 | .... <binary code> .... | MyKey2 |
+---------------+---------+---------------------------+--------------+
The image below shows the binary code.
Hibernate
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) NOT NULL,
`version` varchar(20) NOT NULL,
`examples_name` varchar(120) NOT NULL,
`examples_version` varchar(20) NOT NULL,
`examples_KEY` varchar(255) NOT NULL,
PRIMARY KEY (`name`,`version`,`examples_KEY`),
UNIQUE KEY `UK_o5b5lwcueiue1x7wf2j9l0ohb` (`examples_name`,`examples_version`),
CONSTRAINT `FKeu2s8p9mhstus32uliuwib8rr` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjMapEc` (`name`, `version`),
CONSTRAINT `FKf66pkeal9tdygic4pvspxhph5` FOREIGN KEY (`examples_name`, `examples_version`)
REFERENCES `Example` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
After saving an example (it needs an extra step: save JpaExample objects before JpaExampleObjMapEc object):
MariaDB [controlloop]> select * from ExampleObjMapEc;
+-----------------+---------+
| name | version |
+-----------------+---------+
| ExampleObjMapEc | 1.0.0 |
+-----------------+---------+
MariaDB [controlloop]> select * from Example;
+----------+---------+--------+-----------+
| name | version | primed | timeStamp |
+----------+---------+--------+-----------+
| example1 | 1.0.0 | NULL | NULL |
| example2 | 1.0.0 | NULL | NULL |
+----------+---------+--------+-----------+
MariaDB [controlloop]> select * from JpaExampleObjMapEc_EXAMPLES;
+-----------------+---------+---------------+------------------+--------------+
| name | version | examples_name | examples_version | examples_KEY |
+-----------------+---------+---------------+------------------+--------------+
| ExampleObjMapEc | 1.0.0 | example1 | 1.0.0 | MyKey1 |
| ExampleObjMapEc | 1.0.0 | example2 | 1.0.0 | MyKey2 |
+-----------------+---------+---------------+------------------+--------------+
Map of Objects using ElementCollection (fixed)
The below example shows ElementCollection with embedded class. In order to avoid collisions with field names ("name" and "version"), it has been used AttributeOverride annotation to change their names.
Eclipse-Link
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjMapEc_EXAMPLES;
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| JpaExampleObjMapEc_EXAMPLES | CREATE TABLE `JpaExampleObjMapEc_EXAMPLES` (
`EXAMPLES_KEY` varchar(255) DEFAULT NULL,
`PRIMED` tinyint(1) DEFAULT 0,
`timeStamp` varchar(255) DEFAULT NULL,
`child_name` varchar(255) DEFAULT NULL,
`child_version` varchar(255) DEFAULT NULL,
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) 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 |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
After saving the example:
MariaDB [controlloop]> select * from ExampleObjMapEc;
+---------------+---------+
| name | version |
+---------------+---------+
| ExampleObjMap | 1.0.0 |
+---------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjMapEc_EXAMPLES;
+--------------+--------+-----------+------------+---------------+---------------+---------+
| EXAMPLES_KEY | PRIMED | timeStamp | child_name | child_version | name | version |
+--------------+--------+-----------+------------+---------------+---------------+---------+
| MyKey2 | NULL | NULL | example2 | 1.0.0 | ExampleObjMap | 1.0.0 |
| MyKey1 | NULL | NULL | example1 | 1.0.0 | ExampleObjMap | 1.0.0 |
+--------------+--------+-----------+------------+---------------+---------------+---------+
Hibernate
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjMapEc_EXAMPLES;
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
| JpaExampleObjMapEc_EXAMPLES | CREATE TABLE `JpaExampleObjMapEc_EXAMPLES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`child_name` varchar(255) DEFAULT NULL,
`child_version` varchar(255) DEFAULT NULL,
`primed` bit(1) DEFAULT NULL,
`timeStamp` datetime(6) DEFAULT NULL,
`examples_KEY` varchar(255) NOT NULL,
PRIMARY KEY (`name`,`version`,`examples_KEY`),
CONSTRAINT `FKeu2s8p9mhstus32uliuwib8rr` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjMapEc` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------------+-------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleObjMapEc;
+-----------------+---------+
| name | version |
+-----------------+---------+
| ExampleObjMapEc | 1.0.0 |
+-----------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjMapEc_EXAMPLES;
+-----------------+---------+------------+---------------+--------+-----------+--------------+
| name | version | child_name | child_version | primed | timeStamp | examples_KEY |
+-----------------+---------+------------+---------------+--------+-----------+--------------+
| ExampleObjMapEc | 1.0.0 | example1 | 1.0.0 | NULL | NULL | MyKey1 |
| ExampleObjMapEc | 1.0.0 | example2 | 1.0.0 | NULL | NULL | MyKey2 |
+-----------------+---------+------------+---------------+--------+-----------+--------------+
JpaToscaDataType_PROPERTIES table
The SQL code below shows JpaToscaDataType_PROPERTIES table.
Eclipse-Link
MariaDB [controlloop]> describe JpaToscaDataType_PROPERTIES;
+----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| name | varchar(120) | YES | | NULL | |
| version | varchar(20) | YES | | NULL | |
| PROPERTIES | longblob | YES | | NULL | |
| PROPERTIES_KEY | varchar(255) | YES | | NULL | |
+----------------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SELECT count(1) FROM `JpaToscaDataType_PROPERTIES`;
+----------+
| count(1) |
+----------+
| 41 |
+----------+
MariaDB [controlloop]> describe ToscaProperty;
+------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+--------------+------+-----+---------+-------+
| DEFAULTVALUE | varchar(255) | YES | | NULL | |
| DESCRIPTION | varchar(255) | YES | | NULL | |
| ENTRYSCHEMA | longblob | YES | | NULL | |
| REQUIRED | tinyint(1) | YES | | 0 | |
| STATUS | int(11) | YES | | NULL | |
| parentLocalName | varchar(120) | NO | PRI | NULL | |
| localName | varchar(120) | NO | PRI | NULL | |
| parentKeyVersion | varchar(15) | NO | PRI | NULL | |
| parentKeyName | varchar(120) | NO | PRI | NULL | |
| name | varchar(120) | YES | | NULL | |
| version | varchar(20) | YES | | NULL | |
+------------------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SELECT count(1) FROM ToscaProperty;
+----------+
| count(1) |
+----------+
| 0 |
+----------+
Note
Right now JpaToscaProperty will generate ToscaProperty table but this one will never used. Moving JpaToscaProperty as embeddable class, all max length in varchar fields will be applied.
List of Objects using ElementCollection
ElementCollection should be used with basic type or embeddable class, this example shows side effects using it with entity.
Eclipse-Link
MariaDB [controlloop]> describe ExampleObjListEc;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjListEc_EXAMPLES;
+------------------------------+------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+------------------------------+------------------------------------------------------------------------------------------------------+
| JpaExampleObjListEc_EXAMPLES | CREATE TABLE `JpaExampleObjListEc_EXAMPLES` (
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) DEFAULT NULL,
`EXAMPLES` longblob DEFAULT NULL,
KEY `FK_JpaExampleObjListEc_EXAMPLES_name` (`name`,`version`),
CONSTRAINT `FK_JpaExampleObjListEc_EXAMPLES_name` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjListEc` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+------------------------------+------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleObjListEc;
+-------------+---------+
| name | version |
+-------------+---------+
| ExampleList | 1.0.0 |
+-------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjListEc_EXAMPLES;
+-------------+---------+---------------------------+
| name | version | EXAMPLES |
+-------------+---------+---------------------------+
| ExampleList | 1.0.0 | .... <binary code> .... |
| ExampleList | 1.0.0 | .... <binary code> .... |
+-------------+---------+---------------------------+
Hibernate
MariaDB [controlloop]> describe ExampleObjListEc;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjListEc_EXAMPLES;
+------------------------------+------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+------------------------------+------------------------------------------------------------------------------------------------------+
| JpaExampleObjListEc_EXAMPLES | CREATE TABLE `JpaExampleObjListEc_EXAMPLES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`examples_name` varchar(120) NOT NULL,
`examples_version` varchar(20) NOT NULL,
UNIQUE KEY `UK_8nnxsomci4yiwc8ks6radimiq` (`examples_name`,`examples_version`),
KEY `FK1a58hldurq1910ne2hbm9a7af` (`name`,`version`),
CONSTRAINT `FK1a58hldurq1910ne2hbm9a7af` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjListEc` (`name`, `version`),
CONSTRAINT `FKnj1lga10so090q9wf38k4jf7p` FOREIGN KEY (`examples_name`, `examples_version`)
REFERENCES `Example` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+------------------------------+------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from Example;
+----------+---------+--------+-----------+
| name | version | primed | timeStamp |
+----------+---------+--------+-----------+
| example1 | 1.0.0 | NULL | NULL |
| example2 | 1.0.0 | NULL | NULL |
+----------+---------+--------+-----------+
MariaDB [controlloop]> select * from ExampleObjListEc;
+-------------+---------+
| name | version |
+-------------+---------+
| ExampleList | 1.0.0 |
+-------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjListEc_EXAMPLES;
+-------------+---------+---------------+------------------+
| name | version | examples_name | examples_version |
+-------------+---------+---------------+------------------+
| ExampleList | 1.0.0 | example1 | 1.0.0 |
| ExampleList | 1.0.0 | example2 | 1.0.0 |
+-------------+---------+---------------+------------------+
List of Objects using ElementCollection (fixed)
The below example shows ElementCollection with embedded class.
Eclipse-Link
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjListEc_EXAMPLES;
+------------------------------+------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+------------------------------+------------------------------------------------------------------------------------------------------+
| JpaExampleObjListEc_EXAMPLES | CREATE TABLE `JpaExampleObjListEc_EXAMPLES` (
`PRIMED` tinyint(1) DEFAULT 0,
`timeStamp` varchar(255) DEFAULT NULL,
`child_name` varchar(255) DEFAULT NULL,
`child_version` varchar(255) DEFAULT NULL,
`name` varchar(120) DEFAULT NULL,
`version` varchar(20) DEFAULT NULL,
KEY `FK_JpaExampleObjListEc_EXAMPLES_name` (`name`,`version`),
CONSTRAINT `FK_JpaExampleObjListEc_EXAMPLES_name` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjListEc` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+------------------------------+------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleObjListEc;
+-------------+---------+
| name | version |
+-------------+---------+
| ExampleList | 1.0.0 |
+-------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjListEc_EXAMPLES;
+--------+-----------+------------+---------------+-------------+---------+
| PRIMED | timeStamp | child_name | child_version | name | version |
+--------+-----------+------------+---------------+-------------+---------+
| NULL | NULL | example1 | 1.0.0 | ExampleList | 1.0.0 |
| NULL | NULL | example2 | 1.0.0 | ExampleList | 1.0.0 |
+--------+-----------+------------+---------------+-------------+---------+
Hibernate
MariaDB [controlloop]> SHOW CREATE TABLE JpaExampleObjListEc_EXAMPLES;
+------------------------------+------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+------------------------------+------------------------------------------------------------------------------------------------------+
| JpaExampleObjListEc_EXAMPLES | CREATE TABLE `JpaExampleObjListEc_EXAMPLES` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`child_name` varchar(255) DEFAULT NULL,
`child_version` varchar(255) DEFAULT NULL,
`primed` bit(1) DEFAULT NULL,
`timeStamp` datetime(6) DEFAULT NULL,
KEY `FK1a58hldurq1910ne2hbm9a7af` (`name`,`version`),
CONSTRAINT `FK1a58hldurq1910ne2hbm9a7af` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjListEc` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+------------------------------+------------------------------------------------------------------------------------------------------+
After saving an example:
MariaDB [controlloop]> select * from ExampleObjListEc;
+-------------+---------+
| name | version |
+-------------+---------+
| ExampleList | 1.0.0 |
+-------------+---------+
MariaDB [controlloop]> select * from JpaExampleObjListEc_EXAMPLES;
+-------------+---------+------------+---------------+--------+-----------+
| name | version | child_name | child_version | primed | timeStamp |
+-------------+---------+------------+---------------+--------+-----------+
| ExampleList | 1.0.0 | example1 | 1.0.0 | NULL | NULL |
| ExampleList | 1.0.0 | example2 | 1.0.0 | NULL | NULL |
+-------------+---------+------------+---------------+--------+-----------+
Map of Objects using OneToMany
OneToMany is not used in tosca model template. The example below shows an alternative to ElementCollection. In this example there is a field names collision.
Representation of the example in YAML of what we could save using JpaExampleObjMap entity.
Eclipse-Link
MariaDB [controlloop]> describe ExampleObjMap;
+----------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+--------------+------+-----+---------+-------+
| EXAMPLES | longblob | YES | | NULL | |
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+----------+--------------+------+-----+---------+-------+
After saving the example:
MariaDB [controlloop]> select * from ExampleObjMap;
+--------------------------+---------------+---------+
| EXAMPLES | name | version |
+--------------------------+---------------+---------+
| .... <binary code> .... | ExampleObjMap | 1.0.0 |
+--------------------------+---------------+---------+
Removing @Lob Annotation
The keys name and version of the JpaExampleObjMap as the same as JpaExample, so Eclipse-Link creates a wrong ExampleObjMap_Example table.
MariaDB [controlloop]> describe ExampleObjMap;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| name | varchar(120) | NO | PRI | NULL | |
| version | varchar(20) | NO | PRI | NULL | |
+---------+--------------+------+-----+---------+-------+
MariaDB [controlloop]> SHOW CREATE TABLE ExampleObjMap_Example;
+-----------------------+-------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+-----------------------+-------------------------------------------------------------------------------------------------------------+
| ExampleObjMap_Example | CREATE TABLE `ExampleObjMap_Example` (
`name` varchar(120) NOT NULL,
`version` varchar(20) NOT NULL,
`EXAMPLES_KEY` varchar(255) DEFAULT NULL,
PRIMARY KEY (`name`,`version`),
CONSTRAINT `FK_ExampleObjMap_Example_name` FOREIGN KEY (`name`, `version`)
REFERENCES `ExampleObjMap` (`name`, `version`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |
+-----------------------+-------------------------------------------------------------------------------------------------------------+
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
Map of Objects using OneToMany (fixed)
The example below shows an alternative to ElementCollection with the fix to avoid field names collision.
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 |
+---------------+----------------+------------+---------------+--------------+
Hibernate
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) NOT NULL,
PRIMARY KEY (`parent_name`,`parent_version`,`examples_KEY`),
UNIQUE KEY `UK_ma8t20i58tt5ilqjrk2ged242` (`child_name`,`child_version`),
CONSTRAINT `FK2n1x5g38x55wejkvnvhqin980` FOREIGN KEY (`parent_name`, `parent_version`)
REFERENCES `ExampleObjMap` (`name`, `version`),
CONSTRAINT `FKstwyuf69lrj4tjpafwriuwp3h` FOREIGN KEY (`child_name`, `child_version`)
REFERENCES `Example` (`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;
+----------+---------+--------+-----------+
| name | version | primed | timeStamp |
+----------+---------+--------+-----------+
| example1 | 1.0.0 | NULL | NULL |
| example2 | 1.0.0 | NULL | NULL |
+----------+---------+--------+-----------+
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 |
+---------------+----------------+------------+---------------+--------------+
Multi templates
Right now using Spring repositories it is possible to create more than one service template, as service templates in policy-models/tosca. It works in both Eclipse-Link and Hibernate.
How to create additional service template (just add different name and version into the yaml file):
name: ToscaServiceTemplateSimple version: 1.0.1 tosca_definitions_version: tosca_simple_yaml_1_3 ...........................
In the above example for ToscaNodeTemplate we are using same name and version, so the ToscaNodeTemplates table (and all other tables as well) contains only one record. Using the current entity model definition there are the follow issues:
- There is no way to handle different configuration
- Is impossible to delete a template in cascade, but it needs a Java code to manual delete single records in all tables
At least to avoid the above issues:
- Avoid default name and version (for each template/node/data type, etc.. name and version have to be mandatory)
- Java code to manual check for each table if name and version are already used
Conclusion
- Move to Hibernate with EclipseLink tables is not possible due the presence of ElementCollection not used properly.
- The presence of longblob types used to store whole objects is an issues, it is readable only by Java language or by any other language compatible with Java binary code. I am not sure if a db-migrator can handle that.
- Document databases store all information for a given object in a single instance in the database, and every stored object can be different from every other. So, using MongoDB/Cassandra will solve all issues.
JpaRepository
andMongoRepository
extendCrudRepository
and expose the capabilities of the underlying persistence technology in addition to the rather generic persistence technology-agnostic interfaces like e.g.CrudRepository
.