write read spread

Tuesday, March 16, 2010

why / as sysdba

to start up oracle:

->su -l oracle //login as oracle, password

->sqlplus //start sqlplus

->/ as sysdba //?? see below

->startup //start oracle

->exit //quit sqlplus

http://download.oracle.com/docs/cd/B10501_01/server.920/a90842/ch4.htm#1006252

The AS clause allows privileged connections by users who have been granted SYSOPER or SYSDBA system privileges. You can also use either of these privileged connections with / and /NOLOG.

If you use this option, you need to quote the command arguments on many operating systems, for example:

SQLPLUS "/ AS SYSDBA" SQLPLUS "SYSTEM/your_password AS SYSOPER"

http://ugweb.cs.ualberta.ca/~c391/manual/chapt4.html

Enter the command ``sqlplus /''.
Note: This example assumes that you have been given the same ORACLE user ID as your login. If you forget to add the ``/'' you will be asked to enter your name and password for your ORACLE user ID, in which case you should press $\wedge C$ (cntrl-C) and start over. Entering your system user ID and password will not get you access to SQL*Plus. If your ORACLE user ID differs from your system ID refer to the ``SQL*Plus User's Guide and Reference''.

Sunday, November 29, 2009

Add Model reference to View

In Model View Controller in the context of Cocoa, when View(PolygonView) needs a reference to Model(PolygonShape):
Step 1: declare an instance variable of PolygonShape in PolygonView

Step 2 Link the Outlet PolygonShape to Class PolygonShape

Thursday, October 15, 2009

#include vs #include "file"

First: <> vs ""
Both would work if file exist. The difference is the order of directories are searched.
In case of <>: ONLY searches in list of SYSTEM directories. If file does not exist in the system directories then C1083 error.

In case of "file": First searches in the including file directory(current file directory), if not found then searches in the SYSTEM directories. If either is found then C1083 error.

Second: file vs file.h
Some of the header files end with ".h" others do not. Eg stdio.h vs fstream .Both of the files are in system directory so proper inclusion would be
#include
#include

of course the following would work as well
#include "stdio"
#include "fstream.h"

See picture for more clarification example