跳转到内容
View in the app

A better way to browse. Learn more.

彼岸论坛

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.
欢迎抵达彼岸 彼岸花开 此处谁在 -彼岸论坛

[问与答] 求问:多表 sql 并发生成唯一列数值列

发表于

将 oracle 中的 5 个表同步到 mysql 的 1 个表中; mysql 中需要有一个新增字段(pkm)为 bigint 类型; 这 5 个 oracle 表的数据和数据量会实时变化; 无法改变目标数据源 mysql 的表结构; 现在需要使用 oracle 的 select 语句生成一列新的列,方便抽取到 mysql ; 需要生成的列(pkm)必须是唯一值,不能和其他表重复; 每个 select 是并发执行,不是逐个执行。

所以用 ROW_NUMBER()不太合适,如: SELECT

ROW_NUMBER() OVER (ORDER BY id) +

(SELECT COUNT(*) FROM table1) +

...+

(SELECT COUNT(*) FROM table5)

Featured Replies

No posts to show

创建帐户或登录来提出意见

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.