Configuration
pom-dependent
org.springframework.boot
spring-boot-starter-aop
application.xml configuration
#jpa Configuration
spring.jpa.properties.hibernate.hbm2ddl.auto=update
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.show-sql= true
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl
Note that the last line is used to define the naming policy, if not set, will use the default naming strategy, such as when construction of the table, will have a hump named converted to lowercase, and split with a line such as: the entity class name: userCommon, mapped to a table name is user-common
Use
Use jpa There are two ways, one is to use annotations, another is the use configuration files, these two can be achieved, but it is recommended to use notes, because more concise in this way, and is a major trend, the following describes comment The way.
In entity classes mapped to add the following annotations
@Entity: indicates that the class is an entity class, after adding the annotation can be scanned to jpa
@Table: You can customize the table name
We need to know that the above two lines of notes has been completed jpa mappings, declared after the entity class, which is the default properties of the class will be mapped to the database, but the default is often not meet our requirements, for example, named length, the primary key index are required to specify their own, so the following describes some common notes
Extended Notes
In the Properties Add comment
Primary key:
@Id: generally used to declare a primary key
@GeneratedValue (strategy = GenerationType.IDENTITY): primary key is set to the self-energizing
General Property: Wuxi hospital gynecological examination http://www.87554006.com/
@column: You can customize the column names or other defined data types
比如@column(name=“content”, columnDefinition = “longtext”)
@Transient: no mapping database, similar to the exclusion of
Page directly formatted value type, mainly for the date type
@Temporal(TemporalType.DATE)：如1994-05-06
@Temporal(TemporalType.TIME)：20:46:13
@Temporal(TemporalType.TIMESTAMP)：1994-05-06 20:46:13
The only index
@Table(name = “表名”, uniqueConstraints = {
@UniqueConstraint (name = "Index Name", columnNames = { "Field 1", "Field 2"})
})，
Plus index table index
@Table(name = “表名”,indexes = {
@Index (name = "index name", columnList = "field name")
})
Database initialization
Initialize the database often is often used, we created a database of data generally requires some initialization, configuration is as follows
Increase application.properties profile properties
spring.datasource.data=classpath:database/data.sql
spring.datasource.sql-script-encoding=utf-8
spring.datasource.initialization-mode=ALWAYS
Creating data.sql file, it will execute the sql file when the project started, if the data item has been initialized, it may be the last line of the property instead NEVER ALWAYS