Notice: This Wiki is now read only and edits are no longer possible. Please see: https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/wikis/Wiki-shutdown-plan for the plan.
Difference between revisions of "EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings/Lob"
m |
m |
||
Line 38: | Line 38: | ||
{{EclipseLink_JPA | {{EclipseLink_JPA | ||
− | |previous=[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings/Temporal|Temporal]] | + | |previous=[[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings/Temporal|@Temporal]] |
− | |next= [[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings/Transient|Transient]] | + | |next= [[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings/Transient|@Transient]] |
|up= [[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings|Basic Mappings]] | |up= [[EclipseLink/UserGuide/JPA/Basic JPA Development/Mapping/Basic Mappings|Basic Mappings]] | ||
|version= 2.1.0}} | |version= 2.1.0}} |
Revision as of 11:07, 10 February 2011
EclipseLink | |
Website | |
Download | |
Community | |
Mailing List • Forums • IRC • mattermost | |
Issues | |
Open • Help Wanted • Bug Day | |
Contribute | |
Browse Source |
@Lob
By default, EclipseLink persistence provider assumes that all persistent data can be represented as typical database data types.
Use the @Lob annotation with the @Basic mapping to specify that a persistent property or field should be persisted as a large object to a database-supported large object type.
A Lob may be either a binary or character type. The persistence provider infers the Lob type from the type of the persistent field or property.
For String and character-based types, the default is Clob. In all other cases, the default is Blob.
You can also use the @Column attribute columnDefinition to further refine the Lob type.
For more information, see Section 9.1.5 "Column Annotation" in the JPA Specification.
The @Lob annotation does not have attributes.
This example shows how to use this @Lob annotation to specify that persistent field pic should be persisted as a Blob.
Usage of the @Lob Annotation
@Entity public class Employee implements Serializable { ... @Lob @Basic(fetch=LAZY) @Column(name="EMP_PIC", columnDefinition="BLOB NOT NULL") protected byte[] pic; ... }
For more information, see Section 9.1.20 "Temporal Annotation" in the JPA Specification.