#mybatis常见批量处理
在开发当中,可能经常会遇到批量处理这种情况,一般都再在java层面进行,
其本质是节省数据库连接打开关闭的的次数,占用更少的运行内存。
mybatis批量插入
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< insert id = "saveFeeRuleList" useGeneratedKeys = "true" parameterType = "java.util.List" >
< selectKey resultType = "java.lang.String" keyProperty = "id" order = "AFTER" >
SELECT
LAST_INSERT_ID()
</ selectKey >
INSERT INTO t_product_fee_rule(
< include refid = "Base_Column_List" />
)
VALUES
< foreach collection = "list" item = "item" index = "index" separator = "," >
(
#{item.id},#{item.productId},
#{item.feeCode},#{item.feeValue},
#{item.remarks}
)
</ foreach >
</ insert >
|
mybatis批量删除
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< delete id = "removeProductAgent" parameterType = "java.util.HashMap" >
< foreach collection = "maps.agentIds" item = "item" index = "index" open = "" close = "" separator = ";" >
DELETE FROM t_product_agent
WHERE 1 = 1
AND product_id = #{maps.productId}
AND agent_id = #{item}
</ foreach >
</ delete >
|
此处的maps接口中的@Param值对应,属于自定义变量。
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void removeProductAgent(@Param("maps")Map< String , Object> map);
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mybatis批量修改
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< update id = "saveUpdateFeeRuleList" parameterType = "java.util.List" >
< foreach collection = "list" item = "item" index = "index" open = "" close = "" separator = ";" >
UPDATE t_product_fee_rule
SET
fee_value = #{item.feeValue},
remarks = #{item.remarks}
WHERE id = #{item.id}
</ foreach >
</ update >
|
myBatis mapper文件详解
本文的写作目的主要是带大家了解mapper的写法
表结构:
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CREATE TABLE customer (
id int (11) NOT NULL COMMENT ‘企业用户ID ',
name varchar(45) DEFAULT NULL COMMENT ‘名称' ,
logo varchar (80) DEFAULT ‘ ' COMMENT ‘企业标识' ,
describe varchar (500) DEFAULT ‘ ' COMMENT ‘企业班车说明' ,
is_enable tinyint(1) DEFAULT ‘0 ' COMMENT ‘是否启用 1=启用 0=不启用' ,
phone varchar (20) DEFAULT NULL COMMENT ‘客服电话 ',
admin varchar(50) DEFAULT NULL COMMENT ‘管理员账号' ,
password varchar (80) DEFAULT NULL COMMENT ‘管理员密码 ',
uuid varchar(80) DEFAULT NULL COMMENT ‘企业唯一ID' ,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ;
|
Mapper映射文件是在实际开发过程中使用最多的。
Mapper文件中包含的元素有
-
cache
– 配置给定命名空间的缓存。 -
cache-ref
– 从其他命名空间引用缓存配置。 -
resultMap
– 映射复杂的结果对象。 -
sql
– 可以重用的 SQL 块,也可以被其他语句引用。 -
insert
– 映射插入语句 -
update
– 映射更新语句 -
delete
– 映射删除语句 -
select
– 映射查询语句
本文的代码都是用mybatis-generator生成的注释部分是博主自己加的:
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<? 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">
<!--
namespace绑定了与之对应的接口,值是该接口的全限定名;这个参数有且只有一个
-->
< mapper namespace = "cn.rainbowbus.dao.CustomerMapper" >
<!--
用来描述select语句返回字段与java属性的映射关系。
可以有多个resultMap标签,用不同id区分不同标签。
可以实现一对多,多对多关系
-->
< resultMap id = "BaseResultMap" type = "cn.rainbowbus.entity.Customer" >
<!--
column是表中的字段名。
property是对应的java属性。
jdbcTyep: 数据库中字段类型,它与Java中属性类型有对应关系,详情看下表。
id:数据库主键字段。
result:普通字段。
一对多标签 :
collection> property:对应的java属性名 ofType:对应的java属类型
<id property="java属性" column="author_third_id" jdbcType="BIGINT"/>
<result property="java属性" column="account_id" jdbcType="VARCHAR"/>
-->
< id column = "id" jdbcType = "INTEGER" property = "id" />
< result column = "name" jdbcType = "VARCHAR" javaType = "string" property = "name" />
< result column = "logo" jdbcType = "VARCHAR" property = "logo" />
< result column = "describe" jdbcType = "VARCHAR" property = "describe" />
< result column = "is_enable" jdbcType = "BIT" property = "isEnable" />
< result column = "phone" jdbcType = "VARCHAR" property = "phone" />
< result column = "admin" jdbcType = "VARCHAR" property = "admin" />
< result column = "password" jdbcType = "VARCHAR" property = "password" />
< result column = "uuid" jdbcType = "VARCHAR" property = "uuid" />
</ resultMap >
<!--
可以重用的 SQL 块,也可以被其他语句引用。
-->
< sql id = "Example_Where_Clause" >
< where >/* where 可以自动去除sql语句where关键字后的and关键字*/
/*
向sql传递数组或List, mybatis使用foreach解析,可以做批量处理。
collection:传入的集合的变量名称(要遍历的值)。
item:每次循环将循环出的数据放入这个变量中。
open:循环开始拼接的字符串。
close:循环结束拼接的字符串。
separator:循环中拼接的分隔符。
*/
< foreach collection = "oredCriteria" item = "criteria" separator = "or" >
/*
判断语句,test值等于true执行等于false跳过
test可以是一个值为Boolean型的计算语句
*/
< if test = "criteria.valid" >
/*
前缀'and' 被'(' 替换
prefix:前缀覆盖并增加其内容 不写的话默认替换为空
suffix:后缀覆盖并增加其内容 不写的话默认替换为空
prefixOverrides:前缀判断的条件
suffixOverrides:后缀判断的条件
*/
< trim prefix = "(" prefixOverrides = "and" suffix = ")" >
< foreach collection = "criteria.criteria" item = "criterion" >
/*
choose 是或(or)的关系。
choose标签是按顺序判断其内部when标签中的test条件出否成立,如果有一个成立,则 choose 结束。
当 choose 中所有 when 的条件都不满则时,则执行 otherwise 中的sql。
类似于Java 的 switch 语句,choose 为 switch,when 为 case,otherwise 则为 default。
*/
< choose >
< when test = "criterion.noValue" >
and ${criterion.condition}
</ when >
< when test = "criterion.singleValue" >
and ${criterion.condition} #{criterion.value}
</ when >
< when test = "criterion.betweenValue" >
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
</ when >
< when test = "criterion.listValue" >
and ${criterion.condition}
< foreach close = ")" collection = "criterion.value" item = "listItem" open = "(" separator = "," >
#{listItem}
</ foreach >
</ when >
</ choose >
</ foreach >
</ trim >
</ if >
</ foreach >
</ where >
</ sql >
< sql id = "Update_By_Example_Where_Clause" >
< where >
< foreach collection = "example.oredCriteria" item = "criteria" separator = "or" >
< if test = "criteria.valid" >
< trim prefix = "(" prefixOverrides = "and" suffix = ")" >
< foreach collection = "criteria.criteria" item = "criterion" >
< choose >
< when test = "criterion.noValue" >
and ${criterion.condition}
</ when >
< when test = "criterion.singleValue" >
and ${criterion.condition} #{criterion.value}
</ when >
< when test = "criterion.betweenValue" >
and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
</ when >
< when test = "criterion.listValue" >
and ${criterion.condition}
< foreach close = ")" collection = "criterion.value" item = "listItem" open = "(" separator = "," >
#{listItem}
</ foreach >
</ when >
</ choose >
</ foreach >
</ trim >
</ if >
</ foreach >
</ where >
</ sql >
< sql id = "Base_Column_List" >
< if test = "fields == null" >
id, name, logo, describe, is_enable, phone, admin, password, uuid
</ if >
< if test = "fields != null" >
${fields}
</ if >
</ sql >
<!--
select查询语句标签
id: 与namespace接口中的方法名对应
parameterType: 参数类型
resultMap : 返回值类型
自增IDset到对象中: useGeneratedKeys="true" keyProperty="id" keyColumn="id"
支持类型简写,详情看下表
-->
< select id = "selectByExample" useGeneratedKeys = "true" keyProperty = "id" keyColumn = "id" parameterType = "cn.rainbowbus.entity.CustomerExample" resultMap = "BaseResultMap" >
select
< if test = "distinct" >
distinct
</ if >
< include refid = "Base_Column_List" />/*引入一个SQL模块*/
from customer
< if test = "_parameter != null" >
< include refid = "Example_Where_Clause" />
</ if >
< if test = "orderByClause != null" >
order by ${orderByClause}
</ if >
< if test = "startRow != null" >
limit #{startRow} , #{pageSize}
</ if >
</ select >
< select id = "selectByPrimaryKey" parameterType = "java.lang.Integer" resultMap = "BaseResultMap" >
select
id,name,logo,describe,is_enable,phone,admin,password,uuid
from customer
where id = #{id,jdbcType=INTEGER}
</ select >
<!--
delete删除语句标签
id: 与namespace接口中的方法名对应
parameterType: 参数类型
-->
< delete id = "deleteByPrimaryKey" parameterType = "java.lang.Integer" >
delete from customer
where id = #{id,jdbcType=INTEGER}
</ delete >
< delete id = "deleteByExample" parameterType = "cn.rainbowbus.entity.CustomerExample" >
delete from customer
< if test = "_parameter != null" >
< include refid = "Example_Where_Clause" />
</ if >
</ delete >
<!--插入语句-->
< insert id = "insert" parameterType = "cn.rainbowbus.entity.Customer" >
insert into customer (id, name, logo,
describe, is_enable, phone,
admin, password, uuid
)
values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{logo,jdbcType=VARCHAR},
#{describe,jdbcType=VARCHAR}, #{isEnable,jdbcType=BIT}, #{phone,jdbcType=VARCHAR},
#{admin,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}, #{uuid,jdbcType=VARCHAR}
)
</ insert >
< insert id = "insertSelective" parameterType = "cn.rainbowbus.entity.Customer" >
insert into customer
< trim prefix = "(" suffix = ")" suffixOverrides = "," >
< if test = "id != null" >
id,
</ if >
< if test = "name != null" >
name,
</ if >
< if test = "logo != null" >
logo,
</ if >
< if test = "describe != null" >
describe,
</ if >
< if test = "isEnable != null" >
is_enable,
</ if >
< if test = "phone != null" >
phone,
</ if >
< if test = "admin != null" >
admin,
</ if >
< if test = "password != null" >
password,
</ if >
< if test = "uuid != null" >
uuid,
</ if >
</ trim >
< trim prefix = "values (" suffix = ")" suffixOverrides = "," >
< if test = "id != null" >
#{id,jdbcType=INTEGER},
</ if >
< if test = "name != null" >
#{name,jdbcType=VARCHAR},
</ if >
< if test = "logo != null" >
#{logo,jdbcType=VARCHAR},
</ if >
< if test = "describe != null" >
#{describe,jdbcType=VARCHAR},
</ if >
< if test = "isEnable != null" >
#{isEnable,jdbcType=BIT},
</ if >
< if test = "phone != null" >
#{phone,jdbcType=VARCHAR},
</ if >
< if test = "admin != null" >
#{admin,jdbcType=VARCHAR},
</ if >
< if test = "password != null" >
#{password,jdbcType=VARCHAR},
</ if >
< if test = "uuid != null" >
#{uuid,jdbcType=VARCHAR},
</ if >
</ trim >
</ insert >
< select id = "countByExample" parameterType = "cn.rainbowbus.entity.CustomerExample" resultType = "java.lang.Long" >
select count(*) from customer
< if test = "_parameter != null" >
< include refid = "Example_Where_Clause" />
</ if >
</ select >
< update id = "updateByExampleSelective" parameterType = "map" >
update customer
< set >
< if test = "record.id != null" >
id = #{record.id,jdbcType=INTEGER},
</ if >
< if test = "record.name != null" >
name = #{record.name,jdbcType=VARCHAR},
</ if >
< if test = "record.logo != null" >
logo = #{record.logo,jdbcType=VARCHAR},
</ if >
< if test = "record.describe != null" >
describe = #{record.describe,jdbcType=VARCHAR},
</ if >
< if test = "record.isEnable != null" >
is_enable = #{record.isEnable,jdbcType=BIT},
</ if >
< if test = "record.phone != null" >
phone = #{record.phone,jdbcType=VARCHAR},
</ if >
< if test = "record.admin != null" >
admin = #{record.admin,jdbcType=VARCHAR},
</ if >
< if test = "record.password != null" >
password = #{record.password,jdbcType=VARCHAR},
</ if >
< if test = "record.uuid != null" >
uuid = #{record.uuid,jdbcType=VARCHAR},
</ if >
</ set >
< if test = "_parameter != null" >
< include refid = "Update_By_Example_Where_Clause" />
</ if >
</ update >
< update id = "updateByExample" parameterType = "map" >
update customer
set id = #{record.id,jdbcType=INTEGER},
name = #{record.name,jdbcType=VARCHAR},
logo = #{record.logo,jdbcType=VARCHAR},
describe = #{record.describe,jdbcType=VARCHAR},
is_enable = #{record.isEnable,jdbcType=BIT},
phone = #{record.phone,jdbcType=VARCHAR},
admin = #{record.admin,jdbcType=VARCHAR},
password = #{record.password,jdbcType=VARCHAR},
uuid = #{record.uuid,jdbcType=VARCHAR}
< if test = "_parameter != null" >
< include refid = "Update_By_Example_Where_Clause" />
</ if >
</ update >
< update id = "updateByPrimaryKeySelective" parameterType = "cn.rainbowbus.entity.Customer" >
update customer
< set >
< if test = "name != null" >
name = #{name,jdbcType=VARCHAR},
</ if >
< if test = "logo != null" >
logo = #{logo,jdbcType=VARCHAR},
</ if >
< if test = "describe != null" >
describe = #{describe,jdbcType=VARCHAR},
</ if >
< if test = "isEnable != null" >
is_enable = #{isEnable,jdbcType=BIT},
</ if >
< if test = "phone != null" >
phone = #{phone,jdbcType=VARCHAR},
</ if >
< if test = "admin != null" >
admin = #{admin,jdbcType=VARCHAR},
</ if >
< if test = "password != null" >
password = #{password,jdbcType=VARCHAR},
</ if >
< if test = "uuid != null" >
uuid = #{uuid,jdbcType=VARCHAR},
</ if >
</ set >
where id = #{id,jdbcType=INTEGER}
</ update >
< update id = "updateByPrimaryKey" parameterType = "cn.rainbowbus.entity.Customer" >
update customer
set name = #{name,jdbcType=VARCHAR},
logo = #{logo,jdbcType=VARCHAR},
describe = #{describe,jdbcType=VARCHAR},
is_enable = #{isEnable,jdbcType=BIT},
phone = #{phone,jdbcType=VARCHAR},
admin = #{admin,jdbcType=VARCHAR},
password = #{password,jdbcType=VARCHAR},
uuid = #{uuid,jdbcType=VARCHAR}
where id = #{id,jdbcType=INTEGER}
</ update >
< update id = "batchUpdateByKeys" parameterType = "java.util.List" >
update customer
< trim prefix = "set" suffixOverrides = "," >
< trim prefix = "id =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.id !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.id,jdbcType=INTEGER}
</ if >
< if test = "item.id ==null " >
when #{item.id,jdbcType=INTEGER} then customer.id
</ if >
</ foreach >
</ trim >
< trim prefix = "name =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.name !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.name,jdbcType=VARCHAR}
</ if >
< if test = "item.name ==null " >
when #{item.id,jdbcType=INTEGER} then customer.name
</ if >
</ foreach >
</ trim >
< trim prefix = "logo =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.logo !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.logo,jdbcType=VARCHAR}
</ if >
< if test = "item.logo ==null " >
when #{item.id,jdbcType=INTEGER} then customer.logo
</ if >
</ foreach >
</ trim >
< trim prefix = "describe =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.describe !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.describe,jdbcType=VARCHAR}
</ if >
< if test = "item.describe ==null " >
when #{item.id,jdbcType=INTEGER} then customer.describe
</ if >
</ foreach >
</ trim >
< trim prefix = "is_enable =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.isEnable !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.isEnable,jdbcType=BIT}
</ if >
< if test = "item.isEnable ==null " >
when #{item.id,jdbcType=INTEGER} then customer.is_enable
</ if >
</ foreach >
</ trim >
< trim prefix = "phone =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.phone !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.phone,jdbcType=VARCHAR}
</ if >
< if test = "item.phone ==null " >
when #{item.id,jdbcType=INTEGER} then customer.phone
</ if >
</ foreach >
</ trim >
< trim prefix = "admin =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.admin !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.admin,jdbcType=VARCHAR}
</ if >
< if test = "item.admin ==null " >
when #{item.id,jdbcType=INTEGER} then customer.admin
</ if >
</ foreach >
</ trim >
< trim prefix = "password =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.password !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.password,jdbcType=VARCHAR}
</ if >
< if test = "item.password ==null " >
when #{item.id,jdbcType=INTEGER} then customer.password
</ if >
</ foreach >
</ trim >
< trim prefix = "uuid =case id" suffix = "end," >
< foreach collection = "recordList" index = "index" item = "item" >
< if test = "item.uuid !=null " >
when #{item.id,jdbcType=INTEGER} then #{item.uuid,jdbcType=VARCHAR}
</ if >
< if test = "item.uuid ==null " >
when #{item.id,jdbcType=INTEGER} then customer.uuid
</ if >
</ foreach >
</ trim >
</ trim >
where id in(
< foreach collection = "recordList" index = "index" item = "item" separator = "," >
#{item.id,jdbcType=INTEGER}
</ foreach >
)
</ update >
< insert id = "batchInsert" parameterType = "cn.rainbowbus.entity.Customer" >
insert into customer (id,
name, logo, describe,
is_enable, phone, admin,
password, uuid)
values < foreach collection = "list" item = "item" index = "index" separator = "," > (#{item.id,jdbcType=INTEGER},
#{item.name,jdbcType=VARCHAR}, #{item.logo,jdbcType=VARCHAR}, #{item.describe,jdbcType=VARCHAR},
#{item.isEnable,jdbcType=BIT}, #{item.phone,jdbcType=VARCHAR}, #{item.admin,jdbcType=VARCHAR},
#{item.password,jdbcType=VARCHAR}, #{item.uuid,jdbcType=VARCHAR})</ foreach >
</ insert >
< delete id = "batchDeleteByKeys" parameterType = "java.lang.Integer" >
delete from customer where id in (
< foreach collection = "ids" index = "index" item = "id" separator = "," >
#{id}
</ foreach >
)
</ delete >
</ mapper >
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注意
#{}占位符: 占位
如果传入的是基本类型,那么#{}中的变量名称可以随意写
如果传入的参数是pojo类型,那么#{}中的变量名称必须是pojo中的属性.属性名(user.username)
$ {}拼接符: 字符串原样拼接(有sql注入的风险)
如果传入的是基本类型,那么中 的 变 量 名 必 须 是 v a l u e 如 果 传 入 的 参 数 是 p o j o 类 型 , 那 么 {}中的变量名必须是value 如果传入的参数是pojo类型,那么中的变量名必须是value如果传入的参数是pojo类型,那么{}中的变量名称必须是pojo中的属性.属性名(user.username)
注意:使用拼接符有可能造成sql注入,在页面输入的时候可以加入校验,不可输入sql关键字,不可输入空格
注意:如果是取简单数量类型的参数,括号中的值必须为value
例: select * from user where username like ‘%${value}%'
可以这样写来解决sql注入:select * from user where username like ‘%' #{name}'%'(开发经常使用)
动态SQL
Mybatis提供了9种动态sql标签:trim | where | set | foreach | if | choose | when | otherwise | bind。
1.判断语句if
判断语句,test值等于true执行等于false跳过,test可以是一个值为Boolean型的计算语句
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< if test = "true" > </ if >
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2.修剪语句:trim
- 前缀'and' 被'(' 替换
-
prefix
:前缀覆盖并增加其内容 不写的话默认替换为空 -
suffix
:后缀覆盖并增加其内容 不写的话默认替换为空 -
prefixOverrides
:前缀判断的条件 -
suffixOverrides
:后缀判断的条件
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< trim prefix = "(" suffix = ")" prefixOverrides = "and" ></ trim >
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3.循环语句:foreach
- 向sql传递数组或List, mybatis使用foreach解析,可以做批量处理。
-
collection
:传入的集合的变量名称(要遍历的值)。 -
item
:每次循环将循环出的数据放入这个变量中。 -
open
:循环开始拼接的字符串。 -
close
:循环结束拼接的字符串。 -
separator
:循环中拼接的分隔符。
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< foreach collection = "oredCriteria" item = "criteria" separator = "or" ></ foreach >
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4.选择语句:choose
类似于Java 的 switch 语句,choose 为 switch,when 为 case,otherwise 则为 default。
choose 是或(or)的关系。choose标签是按顺序判断其内部when标签中的test条件出否成立,如果有一个成立,则 choose 结束。当 choose 中所有 when 的条件都不满则时,则执行 otherwise 中的sql。
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< choose >
< when test = "false" >
...
</ when >
< when test = "true" >
...
</ when >
< otherwise >
...同样这不是必须的
</ otherwise >
</ choose >
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mapper对应的Java接口文件:
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package cn.rainbowbus.dao;
import cn.rainbowbus.entity.Customer;
import cn.rainbowbus.entity.CustomerExample;
import java.util.List;
import org.apache.ibatis.annotations.Param;
public interface CustomerMapper {
long countByExample(CustomerExample example);
int deleteByExample(CustomerExample example);
int deleteByPrimaryKey(Integer id);
int insert(Customer record);
int insertSelective(Customer record);
List<Customer> selectByExample(CustomerExample example);
Customer selectByPrimaryKey(Integer id);
int updateByExampleSelective( @Param ( "record" ) Customer record, @Param ( "example" ) CustomerExample example);
int updateByExample( @Param ( "record" ) Customer record, @Param ( "example" ) CustomerExample example);
int updateByPrimaryKeySelective(Customer record);
int updateByPrimaryKey(Customer record);
int batchUpdateByKeys( @Param ( "recordList" ) List<Customer> recordList);
void batchInsert(List<Customer> recordLst);
int batchDeleteByKeys( @Param ( "ids" ) Integer[] ids);
}
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mybatis支持别名:
别名 | 映射类型 |
---|---|
_byte | byte |
_long | long |
_short | short |
_int | int |
_integer | int |
_double | double |
_float | float |
_boolean | boolean |
string | String |
byte | Byte |
long | Long |
short | Short |
int | Integer |
integer | Integer |
double | Double |
float | Float |
boolean | Boolean |
date | Date |
decimal | BigDecimal |
bigdecimal | BigDecimal |
map | Map |
jdbcType与JavaType的映射关系
jdbcType | Java Type |
---|---|
CHAR | String |
ARCHAR | String |
ONGVARCHAR | String |
UMERIC | java.math.BigDecimal |
ECIMAL | java.math.BigDecimal |
IT | boolean |
OOLEAN | boolean |
INYINT | byte |
SMALLINT | short |
INTEGER | int |
BIGINT | long |
REAL | float |
FLOAT | double |
DOUBLE | double |
BINARY | byte[] |
VARBINARY | byte[] |
LONGVARBINARY | byte[] |
DATE | java.sql.Date |
TIME | java.sql.Time |
TIMESTAMP | java.sql.Timestamp |
CLOB | Clob |
BLOB | Blob |
ARRAY | Array |
DISTINCT | mapping of underlying type |
STRUCT | Struct |
REF | Ref |
DATALINK | java.net.URL[color=red][/color] |
以上为个人经验,希望能给大家一个参考,也希望大家多多支持服务器之家。
原文链接:https://zengwei.blog.csdn.net/article/details/72958460