人的意识(Consciousness)由三部分组成,记忆(memory 经验),感观(Sensory),想像和预感(Imagination/prdication),他们有等同的权重.
很多知觉来自于带个人倾向性的预测. 预测又是基于周围环境(上下文),和过去的经历,
太多的经验和带有个人主见的推测将实时感观认知推到了一旁的次要位置.
想像压倒感观认识.
当我们不能保持一个开放的心态,基于事实和数据说话,而是根据个人主观推测,人的思路就容易钻牛角尖.
根据鄙人理解,所谓的分析问题能力(Critical thinking 或者 Analytical and Problem Solving Skills
),指的就是这些.
好了, 理论讲了一大堆, 故事开始了.
客户的一个OLAP数据库满了,需要清理一些过时的历史数据.
通过查询dba_segments,发现LOB大对象占用了80%的空间.
segment_name都是些系统产生的序列号,比如"SYS_LOB0000110879C00036$$".
由于鄙人缺乏LOB知识,不知道table.column和LOB segment的对应关系,也就不知道到底是哪个表的哪个LOB列占用了这么多的存储空间.
我和客户都想着是A表的BLOB_1列占用了太多空间, 可是删除了很多数据以后,回收(shrink)了table和BLOB_1列以后,数据库空间依然占的满满的.
第二天下午遛狗的时候,鄙人才想到可能是我们钻了牛角尖,很可能是另外一个表的LOB列占用了巨大空间,
随即搜索了如何查看LOB列信息,找到了视图user_lobs,也就找到了LOB column name和segment_name的关系, 问题迎刃而解.
具体案例和解决办法,请看http://mujiang.blogspot.com/2010/04/reclaim-deleted-lob-data-storage.html
附录,
个人主见和想象力也有好的一面, 能够加速学习进程.
imagining success is provably effective in achieving it.
You can improve your performance—whether you’re playing a violin,
debugging code, or designing a new architecture—by imagining
that you’ve already done so successfully
From Pragmatic Thinking and Learning
带着朱丽叶在附近的沼泽公园散步.
The Date
June 28th 2009
The Float
Skutz Falls to Marie Canyon - 2hr ride, not including optional time spent beached
Equipment needed
- Tube - If you don't have one, we can buy them at the local tire shop in Duncan for $20 or Zellers in Tillicum Mall has These for $24 (BESTEST TUBE EVEEER!!!!)
- Beverages - What ever you feel like drinking (NO GLASS BOTTLES ALLOWED)
- Cooler(s) - Communal, if anybody has a big cooler that would be great
- Cooler Tube - Gets blown up around the cooler to keep it a float and safe (also acts as an emergency spare)
- River Shoes - I use a old pair of runners, some sort of footware is a must(IMO)
- Rope - Or bungy to tie tubes to the trucks
- Sunscreen!!
- What ever else you might want to bring
The Time Line
- 9 AM - Meet at ABE
- 9:30 AM - Leave for Duncan
- 10:15 AM - Buy Tires and Snacks if wanted
- 10:30 AM - Buy Beverages and head off
- 11:00ish AM - Start Tube ride
- Enter time warp time can not be quantified
The Tubers
- Doug - Have Car will drive
- Megan - Has Car if needed
- Charlie - Will go if I can find someone take care of my puppy and my shin wound recovered.







