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DATAJDBC-285 - Polishing.

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Original pull request: #108.
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Jens Schauder
2019-01-16 16:33:05 +01:00
parent a765b9f214
commit 65de193448
1 changed files with 81 additions and 0 deletions
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src/main/asciidoc/jdbc.adoc
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@@ -190,6 +190,87 @@ Converters should be annotated with `@ReadingConverter` or `@WritingConverter` i
When you use the standard implementations of `CrudRepository` that Spring Data JDBC provides, they expect a certain table structure.
You can tweak that by providing a {javadoc-base}org/springframework/data/relational/core/mapping/NamingStrategy.html[`NamingStrategy`] in your application context.
[[jdbc.entity-persistence.custom-table-name]]
=== `Custom table names`
When the NamingStrategy does not matching on your database table names, you can customize the names with the {javadoc-base}org/springframework/data/relational/core/mapping/Table.html[`@Table`] annotation.
The element `value` of this annotation provides the custom table name. The following example maps the `MyEntity` class to the `CUSTOM_TABLE_NAME` table in the database:
====
[source, java]
----
@Table("CUSTOM_TABLE_NAME")
public class MyEntity {
@Id
Integer id;
String name;
}
----
====
[[jdbc.entity-persistence.custom-column-name]]
=== `Custom column names`
When the NamingStrategy does not matching on your database column names, you can customize the names with the {javadoc-base}org/springframework/data/relational/core/mapping/Column.html[`@Column`] annotation.
The element `value` of this annotation provides the custom column name.
The following example maps the `name` property of the `MyEntity` class to the `CUSTOM_COLUMN_NAME` column in the database:
====
[source, java]
----
public class MyEntity {
@Id
Integer id;
@Column("CUSTOM_COLUMN_NAME")
String name;
}
----
====
The {javadoc-base}org/springframework/data/relational/core/mapping/Column.html[`@Column`] annotation can also be used on a reference type (one-to-one relationship) or on Sets, Lists, and Maps (one-to-many relationship)
On all these types the `value` element of the annotation is used to provide a custom name for the foreign key column referencing the id column in the other table.
In the following example the corresponding table for the `MySubEntity` class has a name column, and the id column of the `MyEntity` id for relationship reasons.
The name of this `MySubEntity` class's id column can also be customized with the `value` element of the {javadoc-base}org/springframework/data/relational/core/mapping/Column.html[`@Column`] annotation:
====
[source, java]
----
public class MyEntity {
@Id
Integer id;
@Column("CUSTOM_COLUMN_NAME")
Set<MySubEntity> name;
}
public class MySubEntity {
String name;
}
----
====
When using `List` and `Map` you must have an additional column for the position of a dataset in the `List` or the key value of the entity in the `Map`.
This additional column name may be customized with the `keyColumn` Element of the {javadoc-base}org/springframework/data/relational/core/mapping/Column.html[`@Column`] annotation:
====
[source, java]
----
public class MyEntity {
@Id
Integer id;
@Column(value = "CUSTOM_COLUMN_NAME", keyColumn = "CUSTOM_KEY_COLUMN_NAME")
List<MySubEntity> name;
}
public class MySubEntity {
String name;
}
----
====
[[jdbc.entity-persistence.state-detection-strategies]]
=== Entity State Detection Strategies