mysql 基本sql使用总结-电商项目

一、增加

1. 设置插入数据后自动返回主键

主键返回策略只适用于单个对象的插入；

主键返回策略：

　　(1) 单独参数

　　　　直接用set方法

　　(2)  map

　　　　对象名.id

　　(3) 多参数列表

　　对象名.id（eg：keyProperty="attr.id"）

eg1: 单独参数

package com.atguigu.mapper;

import java.util.List;
import java.util.Map;

import com.atguigu.bean.T_MALL_PRODUCT;

public interface SpuMapper {

    void insert_spu(T_MALL_PRODUCT spu);

    void insert_images(Map<Object, Object> map);

    List<T_MALL_PRODUCT> select_spu_list(Map<Object, Object> map);

}

<!-- useGeneratedKeys：主键返回策略，默认为false,如果设置为true，则MyBatis插入后的主键返回回去
         keyColumn：数据库生成的主键字段名  keyProperty：实体属性名（指所插入的对象的属性名）-->
    <insert useGeneratedKeys="true" keyColumn="id" keyProperty="id"
        id="insert_spu" parameterType="com.atguigu.bean.T_MALL_PRODUCT">
        insert into t_mall_product
        (
        shp_mch,
        shp_tp,
        flbh1,
        flbh2,
        pp_id,
        shp_msh
        )
        values
        (
        #{shp_mch},
        #{shp_tp},
        #{flbh1},
        #{flbh2},
        #{pp_id},
        #{shp_msh}
        )
    </insert>

eg2: 多参数对象时，需要指定keyProperty="attr.id"，这样MyBatis才知道应该将返回的主键封装给哪个对象

package com.atguigu.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Param;

import com.atguigu.bean.OBJECT_T_MALL_ATTR;
//import com.atguigu.bean.OBJECT_T_MALL_ATTR;
import com.atguigu.bean.T_MALL_VALUE;

public interface AttrMapper {
    /**
     * 保存商品属性
     * @param flbh2
     * @param attr：主键返回策略只适用于单个对象的插入，所以这里需要封装成OBJECT_T_MALL_ATTR对象
     * 这里的insert_attr有两个参数，需要用 @Param,这样主键生成策略中（通过指定keyProperty="attr.id"）
     * 才知道应该将主键封装给哪个参数
     */
    void insert_attr(@Param("flbh2") int flbh2, @Param("attr") OBJECT_T_MALL_ATTR attr);
    /**
     * 插入属性值
     * @param attr_id
     * @param list_value
     */
    void insert_values(@Param("attr_id") int attr_id, @Param("list_value") List<T_MALL_VALUE> list_value);

    List<OBJECT_T_MALL_ATTR> select_attr_list(int flbh2);

}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper SYSTEM "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.atguigu.mapper.AttrMapper">
    <select id="select_attr_list" parameterType="int"
        resultMap="select_attr_list_map">
        select attr.id as attr_id ,attr.*,val.id as val_id ,val.*
        from t_mall_attr attr ,
        t_mall_value val where
        attr.id = val.shxm_id
        and
        attr.flbh2 = #{flbh2}
    </select>
    
    <!-- autoMapping：属性自动映射 -->
    <resultMap type="com.atguigu.bean.OBJECT_T_MALL_ATTR" id="select_attr_list_map"
        autoMapping="true">
        <result column="attr_id" property="id" />
        <collection property="list_value" ofType="com.atguigu.bean.T_MALL_VALUE"
            autoMapping="true">
            <!-- 指定主键映射，其他属性自动映射 -->
            <result column="val_id" property="id" />
        </collection>
        <!-- 如果里面还有对象类型的数据 -->
        <!-- <association property=""></association> -->
        <!-- 如果还有集合类型的数据 -->
        <!-- <collection property=""></collection> -->
    </resultMap>

    <insert id="insert_attr" useGeneratedKeys="true" keyColumn="id"
        keyProperty="attr.id">
        insert into t_mall_attr(
        shxm_mch,
        flbh2
        )
        values
        (
        #{attr.shxm_mch},
        #{flbh2}
        )
    </insert>

    <insert id="insert_values">
        insert into t_mall_value(
        shxzh,
        shxm_id,
        shxzh_mch
        )
        values
        <foreach collection="list_value" item="val" separator=",">
            (
            #{val.shxzh},
            #{attr_id},
            #{val.shxzh_mch}
            )
        </foreach>
    </insert>


</mapper>

2. 批量插入

我传入的参数为map，参数封装：

// 根据spu的主键，批量插入spu图片
Map<Object, Object> map = new HashMap<Object, Object>();
map.put("shp_id", spu.getId());
map.put("list_image", list_image);
spuMapper.insert_images(map);

sql:

    <!-- 插入商品图片 -->
    <insert id="insert_images" parameterType="Map">
        insert into t_mall_product_image(shp_id,url)

        values

        <foreach collection="list_image" item="image" separator=",">
            (#{shp_id},#{image})
        </foreach>
    </insert>

 3.多重对象的同步表单参数提交

A页面表达式ognl(object gram navigation language)

List_attr[0].list_value[0].shxzh  对象.属性.对象的方式去找到对应的属性

B mvc如何封装？

 jsp的表单页面：页面上的级联属性名或者对象名必须在java中要有set方法方法，表单提交时才能自动封装上表单的数据。

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@page isELIgnored="false"  %>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
<%String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath()+"/";%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<base href="<%=basePath %>">
<script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript">
    function b(){}
</script>
<title>硅谷商城</title>
</head>
<body>
    添加商品属性
    <hr>
    <form action="attr_add.do">
        <input type="text" value="${flbh2}" name="flbh2"/>
        <table border="1" width="800px">
            <tr><td>属性名：<input type="text" name="list_attr[0].shxm_mch"/></td><td></td><td>添加属性值</td></tr>
            <tr><td>属性值：<input type="text" name="list_attr[0].list_value[0].shxzh"/></td><td>单位：<input type="text" name="list_attr[0].list_value[0].shxzh_mch"/></td><td>删除</td></tr>
            <tr><td>属性值：<input type="text" name="list_attr[0].list_value[1].shxzh"/></td><td>单位：<input type="text" name="list_attr[0].list_value[1].shxzh_mch"/></td><td>删除</td></tr>
        </table>
        
        <table border="1" width="800px">
            <tr><td>属性名：<input type="text"  name="list_attr[1].shxm_mch"/></td><td></td><td>添加属性值</td></tr>
            <tr><td>属性值：<input type="text"  name="list_attr[1].list_value[0].shxzh"/></td><td>单位：<input type="text" name="list_attr[1].list_value[0].shxzh_mch"/></td><td>删除</td></tr>
            <tr><td>属性值：<input type="text"  name="list_attr[1].list_value[1].shxzh"/></td><td>单位：<input type="text" name="list_attr[1].list_value[1].shxzh_mch"/></td><td>删除</td></tr>
        </table>
        添加：<input type="submit" value="提交"/>
    </form>
</body>
</html>

Controller接收方法：

/**
     * 商品属性提交 （双重集合提交）
     * 页面表达式ognl(object gram navigation language)
     * List_attr[0].list_value[0].shxzh
     * @param flbh2
     * @param list_attr
     * @return
     */
    @RequestMapping("attr_add") 
    public ModelAndView attr_add(int flbh2, MODEL_T_MALL_ATTR list_attr) {

        // 保存属性
        attrServiceInf.save_attr(flbh2, list_attr.getList_attr());

        ModelAndView mv = new ModelAndView("redirect:/index.do");
//        mv.addObject("flbh2", flbh2);
        mv.addObject("url","goto_attr_add.do?flbh2="+flbh2);
        mv.addObject("title","添加属性");
        return mv;
    }

service中的方法：

    /**
     * 保存商品属性
     */
    @Override
    public void save_attr(int flbh2, List<OBJECT_T_MALL_ATTR> list_attr) {
        for (int i = 0; i < list_attr.size(); i++) {
            // 插入属性，返回主键
            OBJECT_T_MALL_ATTR attr = list_attr.get(i);
            attrMapper.insert_attr(flbh2, attr);

            // 获得返回主键批量插入属性值
            attrMapper.insert_values(attr.getId(), attr.getList_value());
        }
    }

实体：

属性值实体：

package com.atguigu.bean;

import java.util.Date;

public class T_MALL_VALUE {

    private int id;
    private String shxzh;
    private String shfqy;
    private int shxm_id;
    private String shxzh_mch;
    private Date chjshj;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getShxzh() {
        return shxzh;
    }

    public void setShxzh(String shxzh) {
        this.shxzh = shxzh;
    }

    public String getShfqy() {
        return shfqy;
    }

    public void setShfqy(String shfqy) {
        this.shfqy = shfqy;
    }

    public int getShxm_id() {
        return shxm_id;
    }

    public void setShxm_id(int shxm_id) {
        this.shxm_id = shxm_id;
    }

    public String getShxzh_mch() {
        return shxzh_mch;
    }

    public void setShxzh_mch(String shxzh_mch) {
        this.shxzh_mch = shxzh_mch;
    }

    public Date getChjshj() {
        return chjshj;
    }

    public void setChjshj(Date chjshj) {
        this.chjshj = chjshj;
    }

}

属性实体：

package com.atguigu.bean;

import java.util.Date;

public class T_MALL_ATTR {

    private int id;
    private String shxm_mch;
    private String shfqy;
    private int flbh2;
    private Date chjshj;


    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getShxm_mch() {
        return shxm_mch;
    }

    public void setShxm_mch(String shxm_mch) {
        this.shxm_mch = shxm_mch;
    }

    public String getShfqy() {
        return shfqy;
    }

    public void setShfqy(String shfqy) {
        this.shfqy = shfqy;
    }

    public int getFlbh2() {
        return flbh2;
    }

    public void setFlbh2(int flbh2) {
        this.flbh2 = flbh2;
    }

    public Date getChjshj() {
        return chjshj;
    }

    public void setChjshj(Date chjshj) {
        this.chjshj = chjshj;
    }

}

商品属性包装对象：将商品的属性和属性值封装为一个对象

package com.atguigu.bean;

import java.util.List;

/**
 * 商品属性包装对象
 * @author doublening
 *
 */
public class OBJECT_T_MALL_ATTR extends T_MALL_ATTR {
    //属性值
    private List<T_MALL_VALUE> list_value;

    public List<T_MALL_VALUE> getList_value() {
        return list_value;
    }

    public void setList_value(List<T_MALL_VALUE> list_value) {
        this.list_value = list_value;
    }

}

商品属性模型实体：这个实体是因为Controller不能直接接收List<OBJECT_T_MALL_ATTR>集合参数而建立的

package com.atguigu.bean;

import java.util.List;

/**
  *  这个对象是对List<OBJECT_T_MALL_ATTR> list_attr的一个封装
  *  因为后端不能直接接收前端传递的list_attr
 * @author doublening
 *
 */
public class MODEL_T_MALL_ATTR {

    private List<OBJECT_T_MALL_ATTR> list_attr;

    public List<OBJECT_T_MALL_ATTR> getList_attr() {
        return list_attr;
    }

    public void setList_attr(List<OBJECT_T_MALL_ATTR> list_attr) {
        this.list_attr = list_attr;
    }

}

二、删除

三、改

四、查

1. 带有集合的实体装配

sql:

<select id="select_attr_list" parameterType="int" resultMap="select_attr_list_map">        
    select attr.id as attr_id ,attr.*,val.id as val_id ,val.*
    from t_mall_attr attr ,
        t_mall_value val where
        attr.id = val.shxm_id
        and
        attr.flbh2 = #{flbh2}
</select>

<!-- autoMapping：属性自动映射 -->
<resultMap type="com.atguigu.bean.OBJECT_T_MALL_ATTR" id="select_attr_list_map"
    autoMapping="true">
    <result column="attr_id" property="id" />
    <collection property="list_value" ofType="com.atguigu.bean.T_MALL_VALUE"
        autoMapping="true">
        <!-- 指定主键映射，其他属性自动映射 -->
        <result column="val_id" property="id" />
    </collection>
    <!-- 如果里面还有对象类型的数据 -->
    <!-- <association property=""></association> -->
    <!-- 如果还有集合类型的数据 -->
    <!-- <collection property=""></collection> -->
</resultMap>

dao层接口：

List<OBJECT_T_MALL_ATTR> select_attr_list(int flbh2);

实体：

// 组合实体
public class OBJECT_T_MALL_ATTR extends T_MALL_ATTR {    
    private List<T_MALL_VALUE> list_value;  
}
// 属性实体
public class T_MALL_ATTR {
    private int id;
    private String shxm_mch;
    private String shfqy;
    private int flbh2;
    private Date chjshj;
}
// 属性值实体
public class T_MALL_VALUE {
    private int id;
    private String shxzh;
    private String shfqy;
    private int shxm_id;
    private String shxzh_mch;
    private Date chjshj;
}    

2. 不带集合的组合装配

xml中的sql:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper SYSTEM "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.atguigu.mapper.ListMapper">
　　 <!-- 通过属性去查库存列表 -->
    <select id="select_list_by_attr" parameterType="Map" resultMap="select_list_by_flbh2_map">
        SELECT
            spu.id as spu_id, spu.*, sku.id as sku_id, sku.*, tm.id as tm_id ,tm.*
        FROM
            t_mall_product spu,
            t_mall_sku sku,
            t_mall_trade_mark tm
        WHERE
            spu.Id = sku.shp_id
            and spu.pp_id = tm.Id
            and spu.flbh2 = #{flbh2}
            ${subSql}
    </select>

    <select id="select_list_by_flbh2" parameterType="int" resultMap="select_list_by_flbh2_map">
        SELECT
            spu.id as spu_id, spu.*, sku.id as sku_id, sku.*, tm.id as tm_id ,tm.*
        FROM
            t_mall_product spu,
            t_mall_sku sku,
            t_mall_trade_mark tm
        WHERE
            spu.Id = sku.shp_id
            and spu.pp_id = tm.Id
            and spu.flbh2 = #{flbh2}
    </select>

    <resultMap type="com.atguigu.bean.OBJECT_T_MALL_SKU" id="select_list_by_flbh2_map" autoMapping="true">
        <id column="sku_id" property="id" />
　　　　　<!--这里的property和组合实体中的属性名一致-->
        <association property="spu" javaType="com.atguigu.bean.T_MALL_PRODUCT" autoMapping="true">
            <id column="spu_id" property="id" />
        </association>
        <association property="tm" javaType="com.atguigu.bean.T_MALL_TRADE_MARK" autoMapping="true">
            <id column="tm_id" property="id" />
        </association>
    </resultMap>
</mapper>

mapper接口:

public interface ListMapper {
    List<OBJECT_T_MALL_SKU> select_list_by_flbh2(int flbh2);
    List<OBJECT_T_MALL_SKU> select_list_by_attr(HashMap<Object, Object> hashMap);
}

实体及其实体关系：

// 组合实体
public class OBJECT_T_MALL_SKU extends T_MALL_SKU {
    private T_MALL_PRODUCT spu;
    private T_MALL_TRADE_MARK tm;
}
// 库存单元实体
public class T_MALL_SKU {
    private int id;
    private int shp_id;
    private int kc;
    private BigDecimal jg;
    private Date chjshj;
    private String sku_mch;
    private String kcdz;
    private long sku_xl;
}
// 产品实体
public class T_MALL_PRODUCT {
    private int id;
    private String shp_mch;
    private String shp_tp;
    private int flbh1;
    private int flbh2;
    private int pp_id;
    private Date chjshj;
    private String shp_msh;
}    
// 交易标识
public class T_MALL_TRADE_MARK {
    private int id;
    private String ppmch;
    private String url;
}    

 参考:

尚硅谷...