先看 xml 结构
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="cn.zdfy.blogsystem.dao.UserMapper">
<select id="queryUserByName" resultType="User" parameterType="String">
SELECT * FROM user WHERE username =#{name}
</select>
</mapper>
先看一下 http://localhost:9290/test?test=“root” 访问,打断点看一下
发现 字符串变成了 “”test”” 导致sql执行时 查不到数据 看sql 日志
2018-04-02 20:28:50.235 WARN 2132 --- [l-1 housekeeper] com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - Thread starvation or clock leap detected (housekeeper delta=2m14s869ms809µs814ns).
2018-04-02 20:28:50.236 DEBUG 2132 --- [io-9290-exec-10] c.z.b.dao.UserMapper.queryUserByName : ==> Preparing: SELECT * FROM user WHERE username =?
2018-04-02 20:28:50.236 DEBUG 2132 --- [io-9290-exec-10] c.z.b.dao.UserMapper.queryUserByName : ==> Parameters: "root"(String)
2018-04-02 20:28:50.237 DEBUG 2132 --- [io-9290-exec-10] c.z.b.dao.UserMapper.queryUserByName : <== Total: 0
再看 http://localhost:9290/test?test=root 访问 断点一下
再看一下 sql日志
2018-04-02 20:30:42.955 WARN 2132 --- [l-1 housekeeper] com.zaxxer.hikari.pool.HikariPool : HikariPool-1 - Thread starvation or clock leap detected (housekeeper delta=1m22s717ms242µs766ns).
2018-04-02 20:30:42.955 DEBUG 2132 --- [nio-9290-exec-2] c.z.b.dao.UserMapper.queryUserByName : ==> Preparing: SELECT * FROM user WHERE username =?
2018-04-02 20:30:42.956 DEBUG 2132 --- [nio-9290-exec-2] c.z.b.dao.UserMapper.queryUserByName : ==> Parameters: root(String)
2018-04-02 20:30:42.957 DEBUG 2132 --- [nio-9290-exec-2] c.z.b.dao.UserMapper.queryUserByName : <== Total: 1