Mybatis-Plus 关于savebatch,saveorupdatebatch遇到的坑及解决办法&拓展mybatisPlus实现类方法，批量插入时，唯一索引冲突后更新

太过爱你忘了你带给我的痛 2023-10-16 09:17 2阅读 0赞

## 一.背景 ##

最近mybatis-plus框架的更新，让我们基础开发中如虎添翼。其中基本的增删改查，代码生成器想必大家用着那叫一个爽。本人在使用中，也遇到一些坑。比如savebatch,saveorupdatebatch，看着这不是批量新增，批量新增或更新嘛，看着api进行开发，感觉也太好用啦。开发完一测试，速度跟蜗牛一样，针对大数据量真是无法忍受。在控制台上发现，怎么名义上是批量插入，还是一条一条的进行插入，难怪速度龟速。

## 二.解决办法 ##

查阅网上资料，大体有两种解决方案：

（1）.使用mybatis的xml,自己进行sql语句编写。该方法一个缺点是如果表的字段较多，有个几十个字段，写批量新增，批量新增修改的sql语句真是个噩梦。

INSERT INTO t 
        (id, age) 
    VALUES 
        (3, 28),
        (4, 29) 
    ON DUPLICATE KEY UPDATE
        id = VALUES(id),
        age = VALUES(age);

(2)mybatis-plus 新添加了一个sql注入器，通过sql注入器可以实现批量新增，批量新增修改功能。一次注入，随时使用，使用极其方便。缺点就是项目启动时候，会进行sql注入器注册，稍微影响启动速度。

## 三.sql注入器实现批量更新，批量插入或更新功能 ##

(1)自定义mapper接口，继承BaseMapper，定义实现的方法。

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import org.apache.ibatis.annotations.Param;
     
    import java.util.List;
     
    /**
     * 根Mapper，给表Mapper继承用的，可以自定义通用方法
     * {@link BaseMapper}
     * {@link com.baomidou.mybatisplus.extension.service.IService}
     * {@link com.baomidou.mybatisplus.extension.service.impl.ServiceImpl}
     */
    public interface RootMapper<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);
     
        /**
         * 自定义批量新增或更新
         * 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 mysqlInsertOrUpdateBath(@Param("list") List<T> list);
     
    }

（2）批量插入、批量新增或更新具体方法实现

批量插入具体方法实现如下：

import com.baomidou.mybatisplus.core.injector.AbstractMethod;
    import com.baomidou.mybatisplus.core.metadata.TableInfo;
    import lombok.extern.slf4j.Slf4j;
    import org.apache.ibatis.executor.keygen.NoKeyGenerator;
    import org.apache.ibatis.mapping.MappedStatement;
    import org.apache.ibatis.mapping.SqlSource;
     
    /**
     * 批量插入方法实现
     */
    @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 -> {
        
                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 -> valueSql.append("#{item.").append(x.getProperty()).append("},"));
            valueSql.delete(valueSql.length() - 1, valueSql.length());
            valueSql.append("</foreach>");
            return valueSql.toString();
        }
    }

批量插入或更新具体方法如下：

import com.baomidou.mybatisplus.core.injector.AbstractMethod;
    import com.baomidou.mybatisplus.core.metadata.TableInfo;
    import org.apache.ibatis.executor.keygen.NoKeyGenerator;
    import org.apache.ibatis.mapping.MappedStatement;
    import org.apache.ibatis.mapping.SqlSource;
    import org.springframework.util.StringUtils;
     
    public class MysqlInsertOrUpdateBath extends AbstractMethod {
        
     
        @Override
        public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
        
            final String sql = "<script>insert into %s %s values %s ON DUPLICATE KEY UPDATE %s</script>";
            final String tableName = tableInfo.getTableName();
            final String filedSql = prepareFieldSql(tableInfo);
            final String modelValuesSql = prepareModelValuesSql(tableInfo);
            final String duplicateKeySql =prepareDuplicateKeySql(tableInfo);
            final String sqlResult = String.format(sql, tableName, filedSql, modelValuesSql,duplicateKeySql);
            //System.out.println("savaorupdatesqlsql="+sqlResult);
            SqlSource sqlSource = languageDriver.createSqlSource(configuration, sqlResult, modelClass);
            return this.addInsertMappedStatement(mapperClass, modelClass, "mysqlInsertOrUpdateBath", sqlSource, new NoKeyGenerator(), null, null);
        }
     
        /**
         * 准备ON DUPLICATE KEY UPDATE sql
         * @param tableInfo
         * @return
         */
        private String prepareDuplicateKeySql(TableInfo tableInfo) {
        
            final StringBuilder duplicateKeySql = new StringBuilder();
            if(!StringUtils.isEmpty(tableInfo.getKeyColumn())) {
        
                duplicateKeySql.append(tableInfo.getKeyColumn()).append("=values(").append(tableInfo.getKeyColumn()).append("),");
            }
     
            tableInfo.getFieldList().forEach(x -> {
        
                duplicateKeySql.append(x.getColumn())
                        .append("=values(")
                        .append(x.getColumn())
                        .append("),");
            });
            duplicateKeySql.delete(duplicateKeySql.length() - 1, duplicateKeySql.length());
            return duplicateKeySql.toString();
        }
     
        /**
         * 准备属性名
         * @param tableInfo
         * @return
         */
        private String prepareFieldSql(TableInfo tableInfo) {
        
            StringBuilder fieldSql = new StringBuilder();
            fieldSql.append(tableInfo.getKeyColumn()).append(",");
            tableInfo.getFieldList().forEach(x -> {
        
                fieldSql.append(x.getColumn()).append(",");
            });
            fieldSql.delete(fieldSql.length() - 1, fieldSql.length());
            fieldSql.insert(0, "(");
            fieldSql.append(")");
            return fieldSql.toString();
        }
     
        private String prepareModelValuesSql(TableInfo tableInfo){
        
            final StringBuilder valueSql = new StringBuilder();
            valueSql.append("<foreach collection=\"list\" item=\"item\" index=\"index\" open=\"(\" separator=\"),(\" close=\")\">");
            if(!StringUtils.isEmpty(tableInfo.getKeyProperty())) {
        
                valueSql.append("#{item.").append(tableInfo.getKeyProperty()).append("},");
            }
            tableInfo.getFieldList().forEach(x -> valueSql.append("#{item.").append(x.getProperty()).append("},"));
            valueSql.delete(valueSql.length() - 1, valueSql.length());
            valueSql.append("</foreach>");
            return valueSql.toString();
        }
    }

（3）sql注入器实现

import com.baomidou.mybatisplus.core.injector.AbstractMethod;
    import com.baomidou.mybatisplus.core.injector.DefaultSqlInjector;
     
    import java.util.List;
     
    /**
     * 自定义方法SQL注入器
     */
    public class CustomizedSqlInjector 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) {
        
            List<AbstractMethod> methodList = super.getMethodList(mapperClass);
            methodList.add(new InsertBatchMethod());
            methodList.add(new UpdateBatchMethod());
            methodList.add(new MysqlInsertOrUpdateBath());
            return methodList;
        }
    }

（4）在自己想使用的mapper上继承自定义的mapper.

import com.sy.adp.common.mybatisPlusExtend.RootMapper;
    import com.sy.adp.flowfull.entity.InfMpmPds;
    import com.baomidou.mybatisplus.core.metadata.IPage;
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import org.apache.ibatis.annotations.Param;
    import org.springframework.stereotype.Component;
     
    @Component
    public interface InfMpmPdsMapper extends RootMapper<InfMpmPds> {
        
     
        IPage<InfMpmPds> selectPageList(Page page, @Param("infMpmPds") InfMpmPds infMpmPds);
     
    }

(5)在controller或serviceImpi中引入mapper,使用自定义的方法。

>>>>>>>>>>>>>>>>>>>>引入mapper>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

![img][]

>>>>>>>>>>>>>>>>>>>>>>>>>方法使用>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

![img][img 1]

完成上述步骤，就可以运行项目进行测试看看，数据提升是不是几个数量级。

--------------------

## 拓展mybatisPlus实现类方法，批量插入时，唯一索引冲突后更新 ##

## 唯一索引注解 ##

package com.zk.fahai.common.annotation;
    
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    
    @Target(ElementType.FIELD)
    @Retention(RetentionPolicy.RUNTIME)
    public @interface FhId {
        }

## 拓展服务类，使用时extend即可 ##

package com.zk.fahai.util;
    
    import com.baomidou.mybatisplus.core.conditions.update.UpdateWrapper;
    import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import com.baomidou.mybatisplus.core.metadata.TableFieldInfo;
    import com.baomidou.mybatisplus.core.metadata.TableInfo;
    import com.baomidou.mybatisplus.core.metadata.TableInfoHelper;
    import com.baomidou.mybatisplus.core.toolkit.Assert;
    import com.baomidou.mybatisplus.core.toolkit.ReflectionKit;
    import com.baomidou.mybatisplus.extension.service.IService;
    import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
    import com.zk.fahai.common.annotation.FhId;
    import com.zk.fx.common.util.JsonUtils;
    import java.io.IOException;
    import java.util.Collection;
    import java.util.List;
    import java.util.stream.Collectors;
    import java.util.stream.Stream;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.dao.DuplicateKeyException;
    import org.springframework.transaction.annotation.Transactional;
    
      /** 批量插入，冲突更新 @param entityList 数据 */
      @Transactional(rollbackFor = Exception.class)
      public void saveOrUpdateBatchByFhId(Collection<T> entityList) throws IOException {
        
        TableInfo tableInfo = TableInfoHelper.getTableInfo(entityClass);
        Assert.notNull(
            tableInfo, "error: can not execute. because can not find cache of TableInfo for entity!");
    
        List<String> ukFieldNameList =
            tableInfo.getFieldList().stream()
                .filter(c -> c.getField().isAnnotationPresent(FhId.class))
                .map(tableFieldInfo -> tableFieldInfo.getField().getName())
                .collect(Collectors.toList());
        if (ukFieldNameList.size() < 1) {
        
          logger.error("未找到唯一索引，class：{}", tableInfo.getEntityType());
          return;
        }
        for (List<T> list : this.cutList(entityList, IService.DEFAULT_BATCH_SIZE)) {
        
          try {
        
            super.saveBatch(list);
          } catch (DuplicateKeyException duplicateKeyException) {
        
            for (T entity : list) {
        
              try {
        
                super.save(entity);
              } catch (DuplicateKeyException e2) {
        
                logger.info("数据更新触发唯一索引，对象：{}", JsonUtils.object2JsonString(entity));
                UpdateWrapper<T> updateWrapper = new UpdateWrapper<>();
                ukFieldNameList.forEach(
                    uk -> updateWrapper.eq(uk, ReflectionKit.getFieldValue(entity, uk)));
                super.update(entity, updateWrapper);
              }
            }
          }
        }
      }
    
      /** 切分集合 */
      public <C> List<List<C>> cutList(Collection<C> list, int maxNum) {
        
        int step = (list.size() + maxNum - 1) / maxNum;
        return Stream.iterate(0, n -> n + 1)
            .limit(step)
            .parallel()
            .map(
                a ->
                    list.stream()
                        .skip(a * maxNum)
                        .limit(maxNum)
                        .parallel()
                        .collect(Collectors.toList()))
            .collect(Collectors.toList());
      }
    }

## 不使用saveBatch版，拓展服务类，使用时extend即可 ##

发现oracle使用savebatch时有问题

package com.zk.fahai.common.annotation;
    
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /**
     * 法海数据唯一索引
     */
    @Target(ElementType.FIELD)
    @Retention(RetentionPolicy.RUNTIME)
    public @interface FhUniqueIndex {
        }

package com.zk.fahai.service.fh;
    
    import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
    import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import com.baomidou.mybatisplus.core.metadata.TableFieldInfo;
    import com.baomidou.mybatisplus.core.metadata.TableInfo;
    import com.baomidou.mybatisplus.core.metadata.TableInfoHelper;
    import com.baomidou.mybatisplus.core.toolkit.Assert;
    import com.baomidou.mybatisplus.core.toolkit.ReflectionKit;
    import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
    import com.zk.fahai.common.annotation.FhUniqueIndex;
    import com.zk.fx.common.util.JsonUtils;
    import java.io.IOException;
    import java.lang.reflect.Field;
    import java.util.List;
    import java.util.stream.Collectors;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.dao.DuplicateKeyException;
    import org.springframework.transaction.annotation.Transactional;
    
    /**
     * 拓展 mybatis-plus方法，数据落库使用
     *
     */
    public class DataStorageExpandService<M extends BaseMapper<T>, T> extends ServiceImpl<M, T> {
        
    
      private static final Logger logger = LoggerFactory.getLogger(DataStorageExpandService.class);
    
      /** 插入，冲突更新 @param entityList 数据 */
      @Transactional(rollbackFor = Exception.class)
      public void saveOrUpdateByFhUk(List<T> entityList) throws IOException {
        
        List<String> fhUkFieldNameList = this.getFhUkFieldNameList();
        for (T entity : entityList) {
        
          this.saveOrUpdateByFhUniqueIndex(fhUkFieldNameList, entity);
        }
      }
    
      /** 插入，冲突更新 @param entity 数据 */
      @Transactional(rollbackFor = Exception.class)
      public void saveOrUpdateByFhUk(T entity) throws IOException {
        
        this.saveOrUpdateByFhUniqueIndex(this.getFhUkFieldNameList(), entity);
      }
    
      private void saveOrUpdateByFhUniqueIndex(List<String> fhUkFieldNameList, T entity)
          throws IOException {
        
        try {
        
          super.save(entity);
        } catch (DuplicateKeyException e2) {
        
          QueryWrapper<T> queryWrapper = new QueryWrapper<>();
          fhUkFieldNameList.forEach(
              ukFieldName -> {
        
                Object ukFieldValue = ReflectionKit.getFieldValue(entity, ukFieldName);
                queryWrapper.eq(ukFieldName, ukFieldValue);
              });
          this.fillId(entity, queryWrapper);
          logger.info("数据保存触发唯一索引，进行更新，数据 ->{}", JsonUtils.object2JsonString(entity));
          super.updateById(entity);
        }
      }
    
      /** 获取主键回填 */
      private void fillId(T entity, QueryWrapper<T> queryWrapper) {
        
        TableInfo tableInfo = TableInfoHelper.getTableInfo(super.entityClass);
        Assert.notNull(
            tableInfo, "error: can not execute. because can not find cache of TableInfo for entity!");
        String keyProperty = tableInfo.getKeyProperty();
        Assert.notEmpty(
            keyProperty, "error: can not execute. because can not find column for id from entity!");
        Long idVal = (Long) ReflectionKit.getFieldValue(super.getOne(queryWrapper), keyProperty);
        try {
        
          Field idField = entity.getClass().getDeclaredField(keyProperty);
          idField.setAccessible(true);
          idField.set(entity, idVal);
        } catch (NoSuchFieldException | IllegalAccessException e) {
        
          logger.error("获取主键回填异常", e);
        }
      }
    
      private List<String> getFhUkFieldNameList() {
        
        TableInfo tableInfo = TableInfoHelper.getTableInfo(super.entityClass);
        Assert.notNull(
            tableInfo, "error: can not execute. because can not find cache of TableInfo for entity!");
        List<TableFieldInfo> tableFieldInfoList =
            tableInfo.getFieldList().stream()
                .filter(c -> c.getField().isAnnotationPresent(FhUniqueIndex.class))
                .collect(Collectors.toList());
        Assert.notEmpty(
            tableFieldInfoList,
            "error: can not execute. because can not find @FhUniqueIndex for entity!");
        List<String> fhUkFieldNameList =
            tableFieldInfoList.stream()
                .map(tableFieldInfo -> tableFieldInfo.getField().getName())
                .collect(Collectors.toList());
        Assert.notEmpty(
            fhUkFieldNameList,
            "error: can not execute. because can not find column for @FhUniqueIndex from entity!");
        return fhUkFieldNameList;
      }
    }

[img]: https://img-blog.csdnimg.cn/20210413222316453.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI4MDI1NDIz,size_16,color_FFFFFF,t_70
[img 1]: https://img-blog.csdnimg.cn/20210413222429603.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI4MDI1NDIz,size_16,color_FFFFFF,t_70