项目基于优秀开源项目：若依
项目背景：项目中牵扯到数据批量导入，为提高性能，先考虑将MybatisPlus伪批量插入增强为真实批量插入
MybatisPlus源码：
MybatisPlus支持批量插入，但是跟踪源码发现底层是将批量插入的数据循环执行了N次单条插入：
IService源码：
@Transactional(rollbackFor = {Exception.class})default boolean saveBatch(Collection<T> entityList) {return this.saveBatch(entityList, 1000);}boolean saveBatch(Collection<T> entityList, int batchSize);
ServiceImpl源码：
@Transactional(rollbackFor = {Exception.class})public boolean saveBatch(Collection<T> entityList, int batchSize) {String sqlStatement = this.getSqlStatement(SqlMethod.INSERT_ONE);return this.executeBatch(entityList, batchSize, (sqlSession, entity) -> {sqlSession.insert(sqlStatement, entity);});}
底层支持增强改造：
1、创建自定义sql注入类：MySqlInjector.java
public class MySqlInjector extends DefaultSqlInjector {public MySqlInjector() {}@Overridepublic List<AbstractMethod> getMethodList(Class<?> mapperClass, TableInfo tableInfo) {List<AbstractMethod> methodList = super.getMethodList(mapperClass, tableInfo);methodList.add(new InsertBatchSomeColumn(i -> i.getFieldFill() != FieldFill.UPDATE));return methodList;}}2、创建自定义Mapper MyBaseMapper.java
public interface MyBaseMapper<T> extends BaseMapper<T> {/*** 批量插入 仅适用于mysql** @param entityList 实体列表* @return 影响行数*/Integer insertBatchSomeColumn(Collection<T> entityList);
}3、业务Mapper实现自定义的Mapper
@Repository
public interface TestMapper extends MyBaseMapper<Test>
{}4、业务中批量插入，使用insertBatchSomeColumn函数
insertBatchSomeColumn(list);5、新建MyBatisPlus配置类,将自定义sql注入 MybatisPlusConfig.java
@Configuration
public class MybatisPlusConfig {@Beanpublic MybatisPlusInterceptor mybatisPlusInterceptor() {MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();//指定使用数据库类型interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));return interceptor;}@Beanpublic DefaultSqlInjector mySqlInjector() {return new MySqlInjector();}}在使用默认MybatisPlus配置默认 sessionFactory时，以上即可
此处基于若依，需要将自定义sessionFactory设置为自定义sql注入器
配置文件位置，参考
framwork模块下config包MyBatisConfig
@Beanpublic SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception{String typeAliasesPackage = env.getProperty("mybatis.typeAliasesPackage");String mapperLocations = env.getProperty("mybatis.mapperLocations");String configLocation = env.getProperty("mybatis.configLocation");typeAliasesPackage = setTypeAliasesPackage(typeAliasesPackage);VFS.addImplClass(SpringBootVFS.class);final MybatisSqlSessionFactoryBean sessionFactory = new MybatisSqlSessionFactoryBean();sessionFactory.setDataSource(dataSource);sessionFactory.setTypeAliasesPackage(typeAliasesPackage);sessionFactory.setMapperLocations(resolveMapperLocations(StringUtils.split(mapperLocations, ",")));sessionFactory.setConfigLocation(new DefaultResourceLoader().getResource(configLocation));//自定义批量插入GlobalConfig globalConfig = new GlobalConfig();GlobalConfig.DbConfig dbConfig = new GlobalConfig.DbConfig();globalConfig.setDbConfig(dbConfig);globalConfig.setSqlInjector(new MySqlInjector());sessionFactory.setGlobalConfig(globalConfig);return sessionFactory.getObject();}基于以上，大功告成。快去试试效果吧
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