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Java 通过ETL过程更新数据库的有效方法?_Java_Database_Performance - Fatal编程技术网

Java 通过ETL过程更新数据库的有效方法?

Java 通过ETL过程更新数据库的有效方法?,java,database,performance,Java,Database,Performance,我有一个从源代码(例如,源代码repo)提取组件的工作流。然后将它们与数据库中的持久化组件进行比较,并传播任何添加、修改和删除。我有以下算法: propagate(components) { // Bulk replace for (component in components) { componentName = component.getName(); if !componentPersistence.get(componentName).eq

我有一个从源代码(例如,源代码repo)提取组件的工作流。然后将它们与数据库中的持久化组件进行比较,并传播任何添加、修改和删除。我有以下算法:

propagate(components) {
    
    // Bulk replace
    for (component in components) {
     componentName = component.getName();
     if !componentPersistence.get(componentName).equals(componentName)
        componentPersistence.update(component);
     else
        componentPersistence.add(component);
    }

    componentPersistence.deleteAllExcept(components);    
}

什么是该计划更有效的实施方式?

我认为有一种方法是这样的:

  • 将所有组件插入临时表(临时组件)

  • 删除临时组件中不存在的所有组件

  • 更新临时组件中存在的所有组件
  • 插入组件表中不存在的所有临时组件
  • 删除临时表

  • 如果您使用的是oracle,则可以通过合并操作进行插入和更新。

    为什么用java标记?
    delete from components c
    where not exists (select 1 from temp_components t where t.name =
    c.name)
    
    update components c
    set field = (select t.field from temp_components t where t.name = c.name)
    where exists (
     select 1 from temp_components t where t.name = c.name
    )
    
    insert into components (name, field)
    select t.name, t.field
    from temp_compoments t
    where not exists (
     select 1 from component c where c.name = t.name
    )