mybatis-plus的批量新增/批量更新以及问题

1.代码中foreach insert/update

 
 for(int i=0;i<insertList.size();i++){
     offerMapper.insert(offerDO);
 }

更新同理

2.多线程foreach insert/update

工作中也使用过多线程批量更新，新增同理

 
//定义线程池
private static final Long KEEP_ALIVE_TIME = 60L;
private static final int APS = Runtime.getRuntime().availableProcessors();
private static final ThreadPoolExecutor THREAD_POOL_EXECUTOR = new ThreadPoolExecutor(
        APS * 2,
        APS * 4,
        KEEP_ALIVE_TIME,
        TimeUnit.SECONDS,
        new LinkedBlockingDeque<>(256),
        new ThreadFactoryBuilder().setNameFormat("分拣出库-pool-%d").build(),
        new ThreadPoolExecutor.CallerRunsPolicy()
);
 
//使用
try {
    taskExecute(list, yearList);
} catch (Exception e) {
    log.error("分拣出库更新失败：{}", e);
}
 
// 处理单个任务数据（year是分库分表用的）
private void taskExecute(List<SortingOutboundProductDetailDO> list, List<Integer> yearList) throws Exception {
    if (CollectionUtils.isEmpty(list)) {
        return;
    }
 
    final CountDownLatch latch = new CountDownLatch(list.size());
    for (SortingOutboundProductDetailDO data : list) {
 
        THREAD_POOL_EXECUTOR.submit(() -> {
            try {
                //更新从表
                sortingOutboundProductDetailMapper.update(null,
                        new LambdaUpdateWrapper<SortingOutboundProductDetailDO>()
                                .eq(SortingOutboundProductDetailDO::getId, data.getId())
                                .in(SortingOutboundProductDetailDO::getYear, yearList)
                                .set(SortingOutboundProductDetailDO::getOutboundNumber, data.getOutboundNumber())
                );
            } finally {
                if (latch != null) {
                    latch.countDown();
                }
            }
        });
    }
    latch.await();
}

3.mybatis xml中foreach

批量新增

 
//不用关注里面的业务代码
private int insert(OfferSaveRequest request){
    List<OfferDO> insertOffer = request.getOfferList().stream().map(obj -> {
        OfferDO offerDO = new OfferDO();
        offerDO.setId(IdWorker.getId());
        offerDO.setFirstSubjectId(request.getFirstSubjectId());
        offerDO.setWarehouseNum(request.getWarehouseNum());
        offerDO.setExpressCompany(obj.getExpressCompany());
        offerDO.setExpressCompanyName(obj.getExpressCompanyName());
        offerDO.setArea(obj.getArea());
        offerDO.setExpensesItemName(obj.getExpensesItemName());
        offerDO.setUnit(obj.getUnit());
        offerDO.setFees(obj.getFees());
        offerDO.setDescription(obj.getDescription());
        offerDO.setTransportType(generateTransportType(obj.getExpensesItemName()));
        offerDO.setCreateTime(new Date());
        offerDO.setCreateUserId(1L);
        offerDO.setCreateUserName("管理员");
        return offerDO;
    }).collect(Collectors.toList());
    return offerMapper.batchInsert(insertOffer);
}

xml

 
<insert id="batchInsert" parameterType="com.model.OfferDO">
    INSERT INTO offer(
    id,
    first_subject_id,
    warehouse_num,
    express_company,
    express_company_name,
    area,
    expenses_item_name,
    unit,
    fees,
    description,
    create_time,
    create_user_id,
    create_user_name
    )
    values
    <foreach collection="offerList" separator="," item="offer">
    (
    #{offer.id},
    #{offer.firstSubjectId},
    #{offer.warehouseNum},
    #{offer.expressCompany},
    #{offer.expressCompanyName},
    #{offer.area},
    #{offer.expensesItemName},
    #{offer.unit},
    #{offer.fees},
    #{offer.description},
    #{offer.createTime},
    #{offer.createUserId},
    #{offer.createUserName}
    )
    </foreach>
</insert>

批量修改

 
//不用关注里面的业务代码
List<OfferSaveRequest.Offer> updateList = request.getOfferList().stream()
    .filter(obj -> obj.getId() != null).collect(Collectors.toList());
if (updateList.size() > 0) {
    List<OfferDO> updateOffer = updateList.stream().map(obj -> {
        OfferDO offerDO = new OfferDO();
        offerDO.setId(obj.getId());
        offerDO.setArea(obj.getArea());
        offerDO.setFees(obj.getFees());
        offerDO.setDescription(obj.getDescription());
        offerDO.setUpdateTime(new Date());
        offerDO.setUpdateUserId(1L);
        offerDO.setUpdateUserName("管理员");
        return offerDO;
    }).collect(Collectors.toList());
    offerMapper.batchUpdate(updateOffer);
}

xml

 
<update id="batchUpdate" parameterType="com.model.OfferDO">
    <foreach collection="offerList" item="offer" separator=";">
        update
        offer
        set
        <if test="offer.area!=null and offer.area!=''">
            area=#{offer.area},
        </if>
        <if test="offer.fees!=null">
            fees=#{offer.fees},
        </if>
        <if test="offer.description!=null and offer.description!=''">
            description=#{offer.description},
        </if>
        update_time=#{offer.updateTime},
        update_user_id=#{offer.updateUserId},
        update_user_name=#{offer.updateUserName}
        where
        id = #{offer.id}
    </foreach>
</update>

批量修改还需要在配置文件中配置&allowMultiQueries=true，否则报错


spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test?useSSL=false&useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8&allowMultiQueries=true

4.mybatis-plus扩展

1.创建sql注入器

 
/**
 * 自定义方法SQL注入器
 * 【注意】这个类名，可以随便命名
 */
public class MyInjector extends DefaultSqlInjector  {
 
    /**
     * 如果只需增加方法，保留MyBatis plus自带方法，
     * 可以先获取super.getMethodList()，再添加add
     */
    @Override
    public List<AbstractMethod> getMethodList(Class<?> mapperClass) {
        // 注意：此SQL注入器继承了DefaultSqlInjector(默认注入器)，调用了DefaultSqlInjector的getMethodList方法，保留了mybatis-plus的自带方法
        List<AbstractMethod> methodList = super.getMethodList(mapperClass);
        methodList.add(new InsertBatchMethod());
        methodList.add(new UpdateBatchMethod());
        return methodList;
    }
 
}

2.注入容器

 
@Configuration
@MapperScan("com.yida.mapper")
public class MybatisPlusPageConfig {
 
    @Bean
    public MyInjector myInjector(){
        return new MyInjector();
    }
}

3.定义通用mapper

 
/**
 * 公共mapper
 * 要实现批量新增/修改 继承此类
 *
 * @param <T>
 */
public interface CommonMapper<T> extends BaseMapper<T> {
 
    /**
     * 自定义批量插入
     * 如果要自动填充，@Param(xx) xx参数名必须是 list/collection/array 3个的其中之一
     */
    int insertBatch(@Param("list") List<T> list);
 
    /**
     * 自定义批量更新，条件为主键
     * 如果要自动填充，@Param(xx) xx参数名必须是 list/collection/array 3个的其中之一
     */
    int updateBatch(@Param("list") List<T> list);
}

4.新增/修改

 
/**
 * 批量新增
 */
@Slf4j
public class InsertBatchMethod extends AbstractMethod {
    /**
     * insert into user(id, name, age) values (1, "a", 17), (2, "b", 18);
     <script>
     insert into user(id, name, age) values
     <foreach collection="list" item="item" index="index" open="(" separator="),(" close=")">
          #{item.id}, #{item.name}, #{item.age}
     </foreach>
     </script>
     */
    @Override
    public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
        final String sql = "<script>insert into %s %s values %s</script>";
        final String fieldSql = prepareFieldSql(tableInfo);
        final String valueSql = prepareValuesSql(tableInfo);
        final String sqlResult = String.format(sql, tableInfo.getTableName(), fieldSql, valueSql);
        log.debug("sqlResult----->{}", sqlResult);
        SqlSource sqlSource = languageDriver.createSqlSource(configuration, sqlResult, modelClass);
        // 第三个参数必须和RootMapper的自定义方法名一致
        return this.addInsertMappedStatement(mapperClass, modelClass, "insertBatch", sqlSource, new NoKeyGenerator(), null, null);
    }
  
    private String prepareFieldSql(TableInfo tableInfo) {
        StringBuilder fieldSql = new StringBuilder();
        fieldSql.append(tableInfo.getKeyColumn()).append(",");
        tableInfo.getFieldList().forEach(x -> {
            //新增时修改字段不填充
            if (!("update_time".equals(x.getColumn()))
                    &&!("update_user_id".equals(x.getColumn()))
                    &&!("update_user_name".equals(x.getColumn()))){
                fieldSql.append(x.getColumn()).append(",");
            }
        });
        fieldSql.delete(fieldSql.length() - 1, fieldSql.length());
        fieldSql.insert(0, "(");
        fieldSql.append(")");
        return fieldSql.toString();
    }
  
    private String prepareValuesSql(TableInfo tableInfo) {
        final StringBuilder valueSql = new StringBuilder();
        valueSql.append("<foreach collection=\"list\" item=\"item\" index=\"index\" open=\"(\" separator=\"),(\" close=\")\">");
        valueSql.append("#{item.").append(tableInfo.getKeyProperty()).append("},");
        tableInfo.getFieldList().forEach(x -> {
            if (!("updateTime".equals(x.getProperty()))
                    &&!("updateUserId".equals(x.getProperty()))
                    &&!("updateUserName".equals(x.getProperty()))){
                valueSql.append("#{item.").append(x.getProperty()).append("},");
            }
        });
        valueSql.delete(valueSql.length() - 1, valueSql.length());
        valueSql.append("</foreach>");
        return valueSql.toString();
    }
}
/**
 * 批量更新方法实现，条件为主键，选择性更新
 */
@Slf4j
public class UpdateBatchMethod extends AbstractMethod {
    /**
     * update user set name = "a", age = 17 where id = 1;
     * update user set name = "b", age = 18 where id = 2;
     <script>
        <foreach collection="list" item="item" separator=";">
            update user
            <set>
                <if test="item.name != null and item.name != ''">
                    name = #{item.name,jdbcType=VARCHAR},
                </if>
                <if test="item.age != null">
                    age = #{item.age,jdbcType=INTEGER},
                </if>
            </set>
            where id = #{item.id,jdbcType=INTEGER}
        </foreach>
     </script>
     */
    @Override
    public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
        String sql = "<script>\n<foreach collection=\"list\" item=\"item\" separator=\";\">\nupdate %s %s where %s=#{%s} %s\n</foreach>\n</script>";
        String additional = tableInfo.isWithVersion() ? tableInfo.getVersionFieldInfo().getVersionOli("item", "item.") : "" + tableInfo.getLogicDeleteSql(true, true);
        String setSql = sqlSet(tableInfo.isWithLogicDelete(), false, tableInfo, false, "item", "item.");
        String sqlResult = String.format(sql, tableInfo.getTableName(), setSql, tableInfo.getKeyColumn(), "item." + tableInfo.getKeyProperty(), additional);
        log.debug("sqlResult----->{}", sqlResult);
        SqlSource sqlSource = languageDriver.createSqlSource(configuration, sqlResult, modelClass);
        // 第三个参数必须和RootMapper的自定义方法名一致
        return this.addUpdateMappedStatement(mapperClass, modelClass, "updateBatch", sqlSource);
    }
  
}

5.使用，将原有的继承BaseMapper的方法，改写为继承CommonMapper，后续批量操作，直接使用新增的两个方法进行处理即可。

 
public interface OfferMapper extends CommonMapper<OfferDO> {
}

新增：offerMapper.insertBatch(insertOffer)

更新：offerMapper.updateBatch(updateOffer)

not null问题

在实际使用中发现一个问题，这个批量插入是在项目启动后就进行拼接好的sql，然后调用的时候，进行值得替换，例

 
<script>
INSERT INTO express (id,express_name,express_code,state,create_time,create_user_id,create_user_name) VALUES <foreach collection="list" item="et" separator=",">
(#{id},#{expressName},#{expressCode},#{state},#{createTime},#{createUserId},#{createUserName})
</foreach>
</script>

发现是全量新增，这样也就产生了一个问题，当只想新增一部分数据，剩下的一部分数据更新进去时，有时会有问题，这取决于你数据库中字段设置是可以为null还是不可以为null。

当数据库中字段设置为not null，而新增的时候传一个null，就会触发数据库的not null校验，报错

然后就查资料，改代码，测试，然后官网上是这样说的

参考：https://blog.csdn.net/weixin_45505313/article/details/121574166

 
Inserting NULL into a column that has been declared NOT NULL. For multiple-row INSERT statements or 
INSERT INTO ... SELECT statements, the column is set to the implicit default value for the column
data type. This is 0 for numeric types, the empty string ('') for string types, and the “zero” value
for date and time types. INSERT INTO ... SELECT statements are handled the same way as multiple-row
inserts because the server does not examine the result set from the SELECT to see whether it returns
a single row. (For a single-row INSERT, no warning occurs when NULL is inserted into a NOT NULL column.
Instead, the statement fails with an error.)
 
在声明为NOT NULL的列中插入NULL。对于多行INSERT语句或
插入…SELECT语句时，该列被设置为该列的隐式默认值
数据类型。数值类型为0，字符串类型为空字符串(")，值为" 0 "
用于日期和时间类型。插入…SELECT语句的处理方式与多行语句相同
插入，因为服务器不检查SELECT的结果集，看它是否返回
单行。(对于单行INSERT，当NULL插入到NOT NULL列时，不会出现警告。
相反，语句失败并报错。)

也就是说mysql允许批量插入时，向not null字段插入null值，mysql会给其赋一个隐藏值

但是在我实测下发现并不行，然后又开始查资料，被我发现了这个

那么我就查了一下我的数据库模式

 
select @@sql_mode;
 
结果：ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION

可以看出我的数据库模式为严格模式，怪不得官网说可以插入null，而我的代码一直报错，排坑之旅任重道远

解决方案：

1.关闭数据库的严格模式（公司的数据库没有权限，这个直接pass掉）

2.手动拼批量插入的sql，拼成如下样子，然后一次请求执行，这样只进行了一次数据库连接，也可以实现批量插入的效果，但是不知道这种多个INSERT语句与单个INSERT和多个VALUES的性能怎么样

 
INSERT INTO `oss` VALUES (1, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:21:33', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (2, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:32:32', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (3, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:33:17', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (4, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:44:30', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (5, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:45:28', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (6, -1, '', '合同导入测试.doc','', '', 0, '', '2022-12-08 16:47:03', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (7, -1, '', '合同导入测试.doc','', '', 0, '', '2022-12-08 16:48:03', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (8, -1, '', '测试用文件.docx', '', '', 1, '', '2022-12-08 16:49:35', 1, '系统管理员', NULL, -1, '');
INSERT INTO `oss` VALUES (9, -1, '', '新建文本文档.doc','', '', 0, '', '2022-12-08 17:12:36', 1, '系统管理员', NULL, -1, '');

	for(int i=0;i<insertList.size();i++){
	offerMapper.insert(offerDO);
	}

	//定义线程池
	private static final Long KEEP_ALIVE_TIME = 60L;
	private static final int APS = Runtime.getRuntime().availableProcessors();
	private static final ThreadPoolExecutor THREAD_POOL_EXECUTOR = new ThreadPoolExecutor(
	APS * 2,
	APS * 4,
	KEEP_ALIVE_TIME,
	TimeUnit.SECONDS,
	new LinkedBlockingDeque<>(256),
	new ThreadFactoryBuilder().setNameFormat("分拣出库-pool-%d").build(),
	new ThreadPoolExecutor.CallerRunsPolicy()
	);

	//使用
	try {
	taskExecute(list, yearList);
	} catch (Exception e) {
	log.error("分拣出库更新失败：{}", e);
	}

	// 处理单个任务数据（year是分库分表用的）
	private void taskExecute(List<SortingOutboundProductDetailDO> list, List<Integer> yearList) throws Exception {
	if (CollectionUtils.isEmpty(list)) {
	return;
	}

	final CountDownLatch latch = new CountDownLatch(list.size());
	for (SortingOutboundProductDetailDO data : list) {

	THREAD_POOL_EXECUTOR.submit(() -> {
	try {
	//更新从表
	sortingOutboundProductDetailMapper.update(null,
	new LambdaUpdateWrapper<SortingOutboundProductDetailDO>()
	.eq(SortingOutboundProductDetailDO::getId, data.getId())
	.in(SortingOutboundProductDetailDO::getYear, yearList)
	.set(SortingOutboundProductDetailDO::getOutboundNumber, data.getOutboundNumber())
	);
	} finally {
	if (latch != null) {
	latch.countDown();
	}
	}
	});
	}
	latch.await();
	}

	//不用关注里面的业务代码
	private int insert(OfferSaveRequest request){
	List<OfferDO> insertOffer = request.getOfferList().stream().map(obj -> {
	OfferDO offerDO = new OfferDO();
	offerDO.setId(IdWorker.getId());
	offerDO.setFirstSubjectId(request.getFirstSubjectId());
	offerDO.setWarehouseNum(request.getWarehouseNum());
	offerDO.setExpressCompany(obj.getExpressCompany());
	offerDO.setExpressCompanyName(obj.getExpressCompanyName());
	offerDO.setArea(obj.getArea());
	offerDO.setExpensesItemName(obj.getExpensesItemName());
	offerDO.setUnit(obj.getUnit());
	offerDO.setFees(obj.getFees());
	offerDO.setDescription(obj.getDescription());
	offerDO.setTransportType(generateTransportType(obj.getExpensesItemName()));
	offerDO.setCreateTime(new Date());
	offerDO.setCreateUserId(1L);
	offerDO.setCreateUserName("管理员");
	return offerDO;
	}).collect(Collectors.toList());
	return offerMapper.batchInsert(insertOffer);
	}

	<insert id="batchInsert" parameterType="com.model.OfferDO">
	INSERT INTO offer(
	id,
	first_subject_id,
	warehouse_num,
	express_company,
	express_company_name,
	area,
	expenses_item_name,
	unit,
	fees,
	description,
	create_time,
	create_user_id,
	create_user_name
	)
	values
	<foreach collection="offerList" separator="," item="offer">
	(
	#{offer.id},
	#{offer.firstSubjectId},
	#{offer.warehouseNum},
	#{offer.expressCompany},
	#{offer.expressCompanyName},
	#{offer.area},
	#{offer.expensesItemName},
	#{offer.unit},
	#{offer.fees},
	#{offer.description},
	#{offer.createTime},
	#{offer.createUserId},
	#{offer.createUserName}
	)
	</foreach>
	</insert>

	//不用关注里面的业务代码
	List<OfferSaveRequest.Offer> updateList = request.getOfferList().stream()
	.filter(obj -> obj.getId() != null).collect(Collectors.toList());
	if (updateList.size() > 0) {
	List<OfferDO> updateOffer = updateList.stream().map(obj -> {
	OfferDO offerDO = new OfferDO();
	offerDO.setId(obj.getId());
	offerDO.setArea(obj.getArea());
	offerDO.setFees(obj.getFees());
	offerDO.setDescription(obj.getDescription());
	offerDO.setUpdateTime(new Date());
	offerDO.setUpdateUserId(1L);
	offerDO.setUpdateUserName("管理员");
	return offerDO;
	}).collect(Collectors.toList());
	offerMapper.batchUpdate(updateOffer);
	}

	<update id="batchUpdate" parameterType="com.model.OfferDO">
	<foreach collection="offerList" item="offer" separator=";">
	update
	offer
	set
	<if test="offer.area!=null and offer.area!=''">
	area=#{offer.area},
	</if>
	<if test="offer.fees!=null">
	fees=#{offer.fees},
	</if>
	<if test="offer.description!=null and offer.description!=''">
	description=#{offer.description},
	</if>
	update_time=#{offer.updateTime},
	update_user_id=#{offer.updateUserId},
	update_user_name=#{offer.updateUserName}
	where
	id = #{offer.id}
	</foreach>
	</update>

	/**
	* 自定义方法SQL注入器
	* 【注意】这个类名，可以随便命名
	*/
	public class MyInjector extends DefaultSqlInjector {

	/**
	* 如果只需增加方法，保留MyBatis plus自带方法，
	* 可以先获取super.getMethodList()，再添加add
	*/
	@Override
	public List<AbstractMethod> getMethodList(Class<?> mapperClass) {
	// 注意：此SQL注入器继承了DefaultSqlInjector(默认注入器)，调用了DefaultSqlInjector的getMethodList方法，保留了mybatis-plus的自带方法
	List<AbstractMethod> methodList = super.getMethodList(mapperClass);
	methodList.add(new InsertBatchMethod());
	methodList.add(new UpdateBatchMethod());
	return methodList;
	}

	}

	@Configuration
	@MapperScan("com.yida.mapper")
	public class MybatisPlusPageConfig {

	@Bean
	public MyInjector myInjector(){
	return new MyInjector();
	}
	}

	/**
	* 公共mapper
	* 要实现批量新增/修改继承此类
	*
	* @param <T>
	*/
	public interface CommonMapper<T> extends BaseMapper<T> {

	/**
	* 自定义批量插入
	* 如果要自动填充，@Param(xx) xx参数名必须是 list/collection/array 3个的其中之一
	*/
	int insertBatch(@Param("list") List<T> list);

	/**
	* 自定义批量更新，条件为主键
	* 如果要自动填充，@Param(xx) xx参数名必须是 list/collection/array 3个的其中之一
	*/
	int updateBatch(@Param("list") List<T> list);
	}

	/**
	* 批量新增
	*/
	@Slf4j
	public class InsertBatchMethod extends AbstractMethod {
	/**
	* insert into user(id, name, age) values (1, "a", 17), (2, "b", 18);
	<script>
	insert into user(id, name, age) values
	<foreach collection="list" item="item" index="index" open="(" separator="),(" close=")">
	#{item.id}, #{item.name}, #{item.age}
	</foreach>
	</script>
	*/
	@Override
	public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
	final String sql = "<script>insert into %s %s values %s</script>";
	final String fieldSql = prepareFieldSql(tableInfo);
	final String valueSql = prepareValuesSql(tableInfo);
	final String sqlResult = String.format(sql, tableInfo.getTableName(), fieldSql, valueSql);
	log.debug("sqlResult----->{}", sqlResult);
	SqlSource sqlSource = languageDriver.createSqlSource(configuration, sqlResult, modelClass);
	// 第三个参数必须和RootMapper的自定义方法名一致
	return this.addInsertMappedStatement(mapperClass, modelClass, "insertBatch", sqlSource, new NoKeyGenerator(), null, null);
	}

	private String prepareFieldSql(TableInfo tableInfo) {
	StringBuilder fieldSql = new StringBuilder();
	fieldSql.append(tableInfo.getKeyColumn()).append(",");
	tableInfo.getFieldList().forEach(x -> {
	//新增时修改字段不填充
	if (!("update_time".equals(x.getColumn()))
	&&!("update_user_id".equals(x.getColumn()))
	&&!("update_user_name".equals(x.getColumn()))){
	fieldSql.append(x.getColumn()).append(",");
	}
	});
	fieldSql.delete(fieldSql.length() - 1, fieldSql.length());
	fieldSql.insert(0, "(");
	fieldSql.append(")");
	return fieldSql.toString();
	}

	private String prepareValuesSql(TableInfo tableInfo) {
	final StringBuilder valueSql = new StringBuilder();
	valueSql.append("<foreach collection=\"list\" item=\"item\" index=\"index\" open=\"(\" separator=\"),(\" close=\")\">");
	valueSql.append("#{item.").append(tableInfo.getKeyProperty()).append("},");
	tableInfo.getFieldList().forEach(x -> {
	if (!("updateTime".equals(x.getProperty()))
	&&!("updateUserId".equals(x.getProperty()))
	&&!("updateUserName".equals(x.getProperty()))){
	valueSql.append("#{item.").append(x.getProperty()).append("},");
	}
	});
	valueSql.delete(valueSql.length() - 1, valueSql.length());
	valueSql.append("</foreach>");
	return valueSql.toString();
	}
	}
	/**
	* 批量更新方法实现，条件为主键，选择性更新
	*/
	@Slf4j
	public class UpdateBatchMethod extends AbstractMethod {
	/**
	* update user set name = "a", age = 17 where id = 1;
	* update user set name = "b", age = 18 where id = 2;
	<script>
	<foreach collection="list" item="item" separator=";">
	update user
	<set>
	<if test="item.name != null and item.name != ''">
	name = #{item.name,jdbcType=VARCHAR},
	</if>
	<if test="item.age != null">
	age = #{item.age,jdbcType=INTEGER},
	</if>
	</set>
	where id = #{item.id,jdbcType=INTEGER}
	</foreach>
	</script>
	*/
	@Override
	public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
	String sql = "<script>\n<foreach collection=\"list\" item=\"item\" separator=\";\">\nupdate %s %s where %s=#{%s} %s\n</foreach>\n</script>";
	String additional = tableInfo.isWithVersion() ? tableInfo.getVersionFieldInfo().getVersionOli("item", "item.") : "" + tableInfo.getLogicDeleteSql(true, true);
	String setSql = sqlSet(tableInfo.isWithLogicDelete(), false, tableInfo, false, "item", "item.");
	String sqlResult = String.format(sql, tableInfo.getTableName(), setSql, tableInfo.getKeyColumn(), "item." + tableInfo.getKeyProperty(), additional);
	log.debug("sqlResult----->{}", sqlResult);
	SqlSource sqlSource = languageDriver.createSqlSource(configuration, sqlResult, modelClass);
	// 第三个参数必须和RootMapper的自定义方法名一致
	return this.addUpdateMappedStatement(mapperClass, modelClass, "updateBatch", sqlSource);
	}

	}

	public interface OfferMapper extends CommonMapper<OfferDO> {
	}

	<script>
	INSERT INTO express (id,express_name,express_code,state,create_time,create_user_id,create_user_name) VALUES <foreach collection="list" item="et" separator=",">
	(#{id},#{expressName},#{expressCode},#{state},#{createTime},#{createUserId},#{createUserName})
	</foreach>
	</script>

	Inserting NULL into a column that has been declared NOT NULL. For multiple-row INSERT statements or
	INSERT INTO ... SELECT statements, the column is set to the implicit default value for the column
	data type. This is 0 for numeric types, the empty string ('') for string types, and the “zero” value
	for date and time types. INSERT INTO ... SELECT statements are handled the same way as multiple-row
	inserts because the server does not examine the result set from the SELECT to see whether it returns
	a single row. (For a single-row INSERT, no warning occurs when NULL is inserted into a NOT NULL column.
	Instead, the statement fails with an error.)

	在声明为NOT NULL的列中插入NULL。对于多行INSERT语句或
	插入…SELECT语句时，该列被设置为该列的隐式默认值
	数据类型。数值类型为0，字符串类型为空字符串(")，值为" 0 "
	用于日期和时间类型。插入…SELECT语句的处理方式与多行语句相同
	插入，因为服务器不检查SELECT的结果集，看它是否返回
	单行。(对于单行INSERT，当NULL插入到NOT NULL列时，不会出现警告。
	相反，语句失败并报错。)

	select @@sql_mode;

	结果：ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION

	INSERT INTO `oss` VALUES (1, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:21:33', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (2, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:32:32', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (3, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:33:17', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (4, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:44:30', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (5, -1, '', '测试用文件.docx', '', '', 0, '', '2022-12-08 16:45:28', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (6, -1, '', '合同导入测试.doc','', '', 0, '', '2022-12-08 16:47:03', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (7, -1, '', '合同导入测试.doc','', '', 0, '', '2022-12-08 16:48:03', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (8, -1, '', '测试用文件.docx', '', '', 1, '', '2022-12-08 16:49:35', 1, '系统管理员', NULL, -1, '');
	INSERT INTO `oss` VALUES (9, -1, '', '新建文本文档.doc','', '', 0, '', '2022-12-08 17:12:36', 1, '系统管理员', NULL, -1, '');