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Managing table(SG 9iR2)-6

1.Different Methods for storing User Data
.Regular tables
Regular table is the most commonly used form of storing user data.
.Partitioned tables
.Index-organized tables
Continue reading Managing table(SG 9iR2)-6

Excel VLOOKUP 函数

从一个数组表(table array)也就是一块选定区域的第一列查找某个值,返回该数组表中同一行中指定列值。

Syntax

VLOOKUP(lookup_value,table_array,col_index_num,range_lookup)

Lookup_value
在数组表第一列要匹配的值,这个值也可以是引用。

Table_aray
两行或者多行数据列。

Col_index_num
指定返回列值。

Range_loopup
指定匹配方式的逻辑值:TRUE 或FALSE
TRUE:精确匹配(exact match)
FALSE:模糊匹配(approximate match)

参考:

http://office.microsoft.com/en-us/excel/HP052093351033.aspx

http://www.excel-tutorials.org

http://www.auditexcel.co.za/vlookup.html

Managing Undo Data(SG 9iR2)-5

Two methods for managing undo data exists
-Automatic Undo Management(The recommended method from 9i)
-Manual Undo Management(The only method available prior to Oracle9i)
Continue reading Managing Undo Data(SG 9iR2)-5

Storage Structure and Relationships(SG 9iR2)-4

1.Type of segments
Segments are space-occupying objects in a database.

Table
The most common means of storing data within a database.
Data within a table segment is stored in on particular order,and the DBA has little control
over the location of rows within the blocks in a table.
Continue reading Storage Structure and Relationships(SG 9iR2)-4

没意思…

          这几天心情非常不好,有时候我在怀疑,我这样固执的选择是不是真的错了?或者生活就是这样,人和人之间就是这样.什么诺言,什么保证,什么真心,可能都只是随便说说罢了.有人让我天天看博客,我看了,可是说的人还不知道看了没有呢.天真……无聊……