-
Recent Posts
Recent Comments
- yangtingkun on 非空字段空值对查询的影响
- Eric Zong on 非空字段空值对查询的影响
- Kamus on Oracle Ace Director
- 设置全局死锁优先级 | yangtingkun on RAC全局死锁检测时间
- ORA-600(krbounotread_noctx)错误 | yangtingkun on ORA-600(krboReadBitmap_badbitmap)错误
Archives
- December 2020
- February 2019
- December 2018
- November 2018
- October 2018
- July 2018
- June 2018
- May 2018
- July 2016
- July 2013
- June 2013
- November 2012
- October 2012
- September 2012
- August 2012
- July 2012
- June 2012
- May 2012
- April 2012
- March 2012
- February 2012
- January 2012
- December 2011
- November 2011
- October 2011
- September 2011
- August 2011
Categories
Meta
Tag Archives: FILTER
非空字段空值对查询的影响
BLOG有三年没有更新了,其实这篇文档也是三年前写的,不过当时没有贴出来,今天看到有人问起,于是分享出来。 这是客户数据库中碰到的一个有意思的问题。 数据库版本为11.2.0.3,客户的DSG同步软件在同步某张表时出现了错误,报错无非插入空值ORA-1400,本来这是一个很简单的问题,但是诊断发现问题比较有意思: SQL> select * from t_def; ID NAME TYPE ———- —————————— ——– 1 a SQL> select * from t_def where type is null; no rows selected SQL> select * from t_def where type is not null; ID NAME … Continue reading