惯性聚合 高效追踪和阅读你感兴趣的博客、新闻、科技资讯
阅读原文 在惯性聚合中打开

推荐订阅源

Martin Fowler
Martin Fowler
Blog — PlanetScale
Blog — PlanetScale
Vercel News
Vercel News
L
LangChain Blog
Google DeepMind News
Google DeepMind News
H
Hackread – Cybersecurity News, Data Breaches, AI and More
F
Fortinet All Blogs
The GitHub Blog
The GitHub Blog
Recent Announcements
Recent Announcements
D
DataBreaches.Net
云风的 BLOG
云风的 BLOG
OSCHINA 社区最新新闻
OSCHINA 社区最新新闻
A
About on SuperTechFans
博客园_首页
N
Netflix TechBlog - Medium
Y
Y Combinator Blog
Hugging Face - Blog
Hugging Face - Blog
Last Week in AI
Last Week in AI
酷 壳 – CoolShell
酷 壳 – CoolShell
B
Blog
Apple Machine Learning Research
Apple Machine Learning Research
罗磊的独立博客
美团技术团队
V
V2EX

博客园 - 简单男人!

rowid 删除重复记录!!! 十条“金玉良言” Oracle优化器(Optimizer)! ORACLE 纯粹行列转换!! oracle 行列统计转换!!! 鱼和水的故事!!! oracle日期函数2! 动态SQL--灵活操作各种数据! 别人的语录! oracle优化,hint的使用! 几米语录 oracle的游标和例子! 几米经典语录! - 简单男人! - 博客园 oracle数据库导入导出命令! 如何完全卸载oracle linux系统下oracle计划任务脚本 oracle表的操作! oracle数据库select的学习! Oracle 条件语句和循环语句的学习(1)
oracle中case语句
简单男人! · 2007-10-24 · via 博客园 - 简单男人!

-- Create table
create table HKB_TEST3
(
  USER_ID     NUMBER(4),
  AGE         NUMBER(4),
  USER_NUMBER NUMBER(4)
)

SQL> select * from hkb_test3;
 
USER_ID   AGE USER_NUMBER
------- ----- -----------
      1    12
      2    14
      3    16
      4    11
例子:

update hkb_test3
   set user_number = (select b.user_number
                        from (select a.user_id,
                                     case
                                       when a.age = 12 then
                                        '6'
                                       when a.age = 14 then
                                        '7'
                                       when a.age = 16 then
                                        '8'
                                       else
                                        '9'
                                     end user_number
                                from hkb_test3 a) b
                       where b.user_id = hkb_test3.user_id);

SQL> commit;
 
Commit complete

SQL> select * from hkb_test3;
 
USER_ID   AGE USER_NUMBER
------- ----- -----------
      1    12           6
      2    14           7
      3    16           9
      4    11           9