Use mapper: --- tkmapper

Introduce dependencies ：

Import dependence

 <!--tkMapper Integrate mybatis+SpringBoot-->
		<dependency>
   			<groupId>tk.mybatis</groupId>
   			<artifactId>mapper-spring-boot-starter</artifactId>
    		<version>2.1.5</version>
		</dependency>

       <!--tkMapper Integrate mybatis-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper</artifactId>
            <version>3.1.2</version>
        </dependency>
      

To configure ：

One 、 Set up TkMapper and GukeMapper Put it in a bag

import tk.mybatis.mapper.common.Mapper;
import tk.mybatis.mapper.common.MySqlMapper;
public interface TkMapper<T> extends Mapper<T>, MySqlMapper<T> {
    
}

GukeMapper Inherit TkMapper Use

public interface GukeMapper extends TkMapper<Guke>{
    
}

Database corresponds to entity class ：

import javax.persistence.Column;
import javax.persistence.Id;
import javax.persistence.Table;
@Table(name = " Table name ")
public class Guke{
    
	// Primary key automatic hump mapping 
	@Id     // Primary key ID  Fields in the table  test_id
// @GeneratedValue(strategy = GenerationType.AUTO)// Automatically switch the primary key generation strategy according to the underlying database 
    
    @GeneratedValue(strategy = GenerationType.IDENTITY)// Use mysql The primary key generation strategy of 
// @GeneratedValue(strategy = GenerationType.SEQUENCE)// Use Oracle The primary key generation strategy of 
    private Integer id;
    
	private String testId;  
	@Id     // Primary key ID  Fields in the table  test_no
	private String testNo;
	@Column(name = "name_no")
	private String nameNo;
	get/set
}

Four 、 Add scanning in the startup class TestMapper

@tk.mybatis.spring.annotation.MapperScan("com.swhysc.mapper.*")

Common methods and precautions ：

 public interface BaseMapper<T> extends tk.mybatis.mapper.common.BaseMapper<T>, IdsMapper<T>, MySqlMapper<T>, OracleMapper<T> {
    

 }

notes ： For demonstration, we also quote MySqlMapper and OracleMapper Normally, only one method can be cited because they have the same method insertList(List list), When using, it will report errors

Generic ( Entity class ) The type of must meet the requirements
Entity classes are converted to database tables according to the following rules , Notes are all JPA The annotations in :

1. The table name uses the class name by default , Hump underline ( Only uppercase letters are processed ), Such as UserInfo The default corresponding table name is user_info.
2. The table name can use @Table(name = “tableName”) Make a designation , For those that do not conform to the first default rule, you can specify the table name in this way .
3. Fields default to and @Column equally , Will be used as table fields , The table field defaults to Java Object's Field Name hump to underline .
4. have access to @Column(name = “fieldName”) The designation does not conform to article 3 Field name of rule .
5. Use @Transient Annotations can ignore fields , Fields with this annotation will not be used as table fields .
6. The suggestion must be that there is one @Id Annotate the field as the primary key , There can be multiple @Id Annotated fields are used as joint primary keys .
7. // Primary key automatic hump mapping
   @Id // Primary key ID Fields in the table test_id
   // @GeneratedValue(strategy = GenerationType.AUTO)// Automatically switch the primary key generation strategy according to the underlying database
   @GeneratedValue(strategy = GenerationType.IDENTITY)// Use mysql The primary key generation strategy of
   // @GeneratedValue(strategy = GenerationType.SEQUENCE)// Use Oracle The primary key generation strategy of
   private Integer id;
   be-all mapper Inheriting this class will have the following general methods
   Query methods

BaseSelectMapper General method under

Method name	effect
List selectAll();	Query all data
oolean existsWithPrimaryKey(Object key);	Query whether this primary key exists through the primary key
T selectByPrimaryKey(Object key);	Query by primary key
–	–
T selectOne(T record);	Query single data through entities
–	–
List select(T record);	Query multiple data through entities
–	–
int selectCount(T record);	Query the number of entities through entities

SelectByIdsMapper General method under

Method name	effect
List selectByIds(String var1);	Query data through multiple primary keys