mybatis annotation dynamic sql implementation

There are 2 ways to implement mybatis dynamic sql.

1: script tag

@Select("<script> " +
            "SELECT id, name, email,password " +
            "FROM user " +
            " <where> " +
            " <if test=\"email != null\">id=#{email}</if> " +
            " <if test=\"name != null\"> AND name=#{name}</if> " +
            " </where> " +
            " </script> ")

 At the same time, LIKE cannot be used directly, which can be implemented with the help of the concat function.

@Select("SELECT name from user WHERE email LIKE concat(#{prefix},'%') limit 5")

 

 

2 Use complex annotation classes. Such as: @InsertProvider, @UpdateProvider, @DeleteProvider and @SelectProvider, these are to create dynamic languages ​​and let MyBatis execute these languages.

Now let's look at an example of how to use @SelectProvider to create a simple SELECT map. Create a TutorDynaSqlProvider. Java class with a findTutorByIdSql() method.

 

package com.owen.mybatis.sqlproviders;
import org.apache.ibatis.jdbc.SQL;
public class TutorDynaSqlProvider
{
public String findTutorByIdSql(int tutorId)
{
return "SELECT TUTOR_ID AS tutorId, NAME, EMAIL FROM TUTORS
WHERE TUTOR_ID=#{tutorId}";
} }

 

@SelectProvider(type=TutorDynaSqlProvider.class,
method="findTutorByIdSql")
Tutor findTutorById(int tutorId);

 

 

refer to:

wrote

Dynamic SQL statement for MyBatis annotation application