第二节mybaties 增删查改

1.创建 student表
create table student (stuno number, stuname varchar2(20),stuage number,graname varchar2(20));
 insert into student values (1,'zs',23,'g1'); commit ;
2.创建对象
package org.lanqiao.entity;

import java.math.BigDecimal;

public class Student {
    
    private BigDecimal stuNo;
    private String stuName;
    private BigDecimal stuAge;
    private String graName;
    public Student(BigDecimal stuNo, String stuName, BigDecimal stuAge, String graName) {
        super();
        this.stuNo = stuNo;
        this.stuName = stuName;
        this.stuAge = stuAge;
        this.graName = graName;
    }
    @Override
    public String toString() {
        return "Student [stuNo=" + stuNo + ", stuName=" + stuName + ", stuAge=" + stuAge + ", graName=" + graName + "]";
    }
    public BigDecimal getStuNo() {
        return stuNo;
    }
    public void setStuNo(BigDecimal stuNo) {
        this.stuNo = stuNo;
    }
    public String getStuName() {
        return stuName;
    }
    public void setStuName(String stuName) {
        this.stuName = stuName;
    }
    public BigDecimal getStuAge() {
        return stuAge;
    }
    public void setStuAge(BigDecimal stuAge) {
        this.stuAge = stuAge;
    }
    public String getGraName() {
        return graName;
    }
    public void setGraName(String graName) {
        this.graName = graName;
    }

}
3.创建映射文件studentMapper.xml
<?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="org.lanqiao.entity.studentMapper">
    <!-- parameterMap：输入参数 resultType：返回参数（对象） -->
    <select id="selectStudentById" resultType="org.lanqiao.entity.Student" parameterType="int">
        select * from student where stuno = #{stuno}
    </select>
</mapper>
4.conf.xml 加载映射文件
<mapper resource="org/lanqiao/entity/studentMapper.xml" />
5.增加  http://mybatis.org/dtd/mybatis-3-config.dtd 
eclipse--->preference --->xmllog--->add-->fileSystem
PUBLIC "-//mybatis.org//DTD Config 3.0//EN
6.配置文件
<?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="org.lanqiao.entity.studentMapper">
    <!-- parameterMap：输入参数 resultType：返回参数（对象） -->
    <!-- <select id="selectStudentById" resultType="org.lanqiao.entity.Student" parameterType="int">
        select * from student where stuno = #{stuno}
    </select> -->
    
    <insert id="addstudent"  parameterType="org.lanqiao.entity.Student">
       insert into student (stuNo ,stuName ,stuAge,graName) values(#{stuNo},#{stuName},#{stuAge},#{graName})
    </insert>
    <update id="updatestudent"></update>
    
    <delete id="deleteStudentById" parameterType="int">
        delete from student where stuNo = ${value}
    </delete>
    <!-- 返回值是对象 一个多个resultType都是对象 -->
    <select id="selectStudentAll" resultType="org.lanqiao.entity.Student" >
        select * from student 
    </select>