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- Hibernate Generates Default Primary Key 2017
- Hibernate Generates Default Primary Keys
- Hibernate Generates Default Primary Key Access
- Hibernate Generates Default Primary Key Mean
- Hibernate Generates Default Primary Key Id Field
The <generator> class is a sub-element of id. It is used to generate the unique identifier for the objects of persistent class. There are many generator classes defined in the Hibernate Framework.
There are many generator classes defined in the Hibernate Framework. All the generator classes implements the org.hibernate.id.IdentifierGenerator interface. The application programmer may create one's own generator classes by implementing the IdentifierGenerator interface. Hibernate framework provides many built-in generator classes: assigned.
All the generator classes implements the org.hibernate.id.IdentifierGenerator interface. The application programmer may create one's own generator classes by implementing the IdentifierGenerator interface. Hibernate framework provides many built-in generator classes:
- assigned
- increment
- sequence
- hilo
- native
- identity
- seqhilo
- uuid
- guid
- select
- foreign
- sequence-identity
1) assigned
It is the default generator strategy if there is no <generator> element . In this case, application assigns the id. For example:
2) increment
It generates the unique id only if no other process is inserting data into this table. It generates short, int or long type identifier. If a table contains an identifier then the application considers its maximum value else the application consider that the first generated identifier is 1. For each attribute value, the hibernate increment the identifier by 1. Syntax:
3) sequence
It uses the sequence of the database. if there is no sequence defined, it creates a sequence automatically e.g. in case of Oracle database, it creates a sequence named HIBERNATE_SEQUENCE. In case of Oracle, DB2, SAP DB, Postgre SQL or McKoi, it uses sequence but it uses generator in interbase. Generate public key from ppk mac. Syntax:
For defining your own sequence, use the param subelement of generator.
4) hilo
It uses high and low algorithm to generate the id of type short, int and long. Syntax:
5) native
It uses identity, sequence or hilo depending on the database vendor. Syntax:
6) identity
It is used in Sybase, My SQL, MS SQL Server, DB2 and HypersonicSQL to support the id column. The returned id is of type short, int or long. It is responsibility of database to generate unique identifier.
Hibernate Generates Default Primary Key 2017
7) seqhilo
Hibernate Generates Default Primary Keys
It uses high and low algorithm on the specified sequence name. The returned id is of type short, int or long.
8) uuid
Hibernate Generates Default Primary Key Access
It uses 128-bit UUID algorithm to generate the id. The returned id is of type String, unique within a network (because IP is used). The UUID is represented in hexadecimal digits, 32 in length. Office 2016 key generator online no survey.
9) guid
It uses GUID generated by database of type string. It works on MS SQL Server and MySQL. |
10) select
It uses the primary key returned by the database trigger. |
Hibernate Generates Default Primary Key Mean
11) foreign
It uses the id of another associated object, mostly used with <one-to-one> association. |
12) sequence-identity
It uses a special sequence generation strategy. It is supported in Oracle 10g drivers only. |
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