MyBatis learning summary (6) - calling stored procedures

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First, put forward the demand

　　Query to get the number of males or females, if the input is 0, it is female, otherwise it is male

Second, prepare database tables and stored procedures

 1 create table p_user(  
 2     id int primary key auto_increment,  
 3     name varchar(10),
 4     sex char(2)
 5 ); 
 6 
 7 insert into p_user(name,sex) values('A',"男");  
 8 insert into p_user(name,sex) values('B',"女");  
 9 insert into p_user(name,sex) values('C',"男");  
10 
11 -- 创建存储过程(查询得到男性或女性的数量, 如果传入的是0就女性否则是男性)
12 DELIMITER $
13 CREATE PROCEDURE mybatis.ges_user_count(IN sex_id INT, OUT user_count INT)
14 BEGIN  
15 IF sex_id=0 THEN
16 SELECT COUNT(*) FROM mybatis.p_user WHERE p_user.sex='女' INTO user_count;
17 ELSE
18 SELECT COUNT(*) FROM mybatis.p_user WHERE p_user.sex='男' INTO user_count;
19 END IF;
20 END 
21 $
22 
23 -- 调用存储过程
24 DELIMITER ;
25 SET @user_count = 0;
26 CALL mybatis.ges_user_count(1, @user_count);
27 SELECT @user_count;

3. Edit userMapper.xml

　　Edit the userMapper.xml file and add the following configuration items

 1 <!-- 
 2         查询得到男性或女性的数量, 如果传入的是0就女性否则是男性
 3      -->
 4     <select id="getUserCount" parameterMap="getUserCountMap" statementType="CALLABLE">
 5         CALL mybatis.ges_user_count(?,?)
 6     </select>
 7     
 8     <!--
 9         parameterMap.put("sexid", 0);
10         parameterMap.put("usercount", -1);
11      -->
12     <parameterMap type="java.util.Map" id="getUserCountMap">
13         <parameter property="sexid" mode="IN" jdbcType="INTEGER"/>
14         <parameter property="usercount" mode="OUT" jdbcType="INTEGER"/>
15     </parameterMap>

Fourth, write unit test code

 1 package me.gacl.test;
 2 
 3 import java.util.HashMap;
 4 import java.util.List;
 5 import java.util.Map;
 6 
 7 import me.gacl.custom.model.ConditionUser;
 8 import me.gacl.domain.User;
 9 import me.gacl.util.MyBatisUtil;
10 import org.apache.ibatis.session.SqlSession;
11 import org.junit.Test;
12 
13 /**
14  * @author gacl
15  * 测试调用存储过程
16  */
17 public class Test6 {
18     
19     @Test
20     public void testGetUserCount(){
21         SqlSession sqlSession = MyBatisUtil.getSqlSession();
22         /**
23          * 映射sql的标识字符串，
24          * me.gacl.mapping.userMapper是userMapper.xml文件中mapper标签的namespace属性的值，
25          * getUserCount是select标签的id属性值，通过select标签的id属性值就可以找到要执行的SQL
26          */
27         String statement = "me.gacl.mapping.userMapper.getUserCount";//映射sql的标识字符串
28         Map<String, Integer> parameterMap = new HashMap<String, Integer>();
29         parameterMap.put("sexid", 1);
30         parameterMap.put("usercount", -1);
31         sqlSession.selectOne(statement, parameterMap);
32         Integer result = parameterMap.get("usercount");
33         System.out.println(result);
34         sqlSession.close();
35     }
36 }

 

Reprinted in: https://my.oschina.net/zhanghaiyang/blog/606211