<?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="com.example.dahua.dao.UserDao"> <!--<select id="getStudentNum" resultType="String" parameterType="String">--> <!--select student_num--> <!--from SZ_V_School_Student--> <!--where school_id = #{school_id}--> <!--and studentcode = #{studentcode}--> <!--</select>--> <select id="getStudentWiSidAndSex" resultType="java.lang.String"> select student_num from SZ_V_School_Student where school_id = #{schoolId} and sex in <foreach collection="sexs" item="sex" index="index" open="(" separator="," close=")"> #{sex} </foreach> </select> </mapper>