How to open linux folders in the same window?

Default behavior while opening folders in Linux, meant, a new window for each folder I double-clicked on. To prevent that, and to ensure Linux opens folders in the same window, I followed the steps listed below:
Go to home folder (Screen -1)

Screen -1

Select Edit from the Menu and scroll down to click on Preferences (Screen -2)

Screen -2

Click on Behavior Tab and select "Always open in browser window" (Screen -3)

Screen -3

The explorer view is shown below (Screen -4)

Screen -4

conversion differences between TO_NUMBER and TO_CHAR

It was interesting to note that what works in TO_CHAR conversion does not in TO_NUMBER. For TO_CHAR, I passed 12.56 for parameter1 and '999.9' for parameter2. It returned 12.6(has obviously rounded it up. Whereas, try it for TO_NUMBER, ORACLE returned an error ORA-01722

SQL Developer History

SQL Developer History

History of commands is handled very well in SQLDeveloper. Pressing F8 will display the history of sql commands that has been issued till now. Place the cursor in the SQL Window, and press "Ctrl+Up arrow" or "Ctrl + down arrow", to paste commands in the history tab into the SQL Window. This works very well, except for the last row or the first row, when the up or down arrow will takes me nowhere. For either of these two situations, I either grab the SQL, from the History window, with cursor and drop it in the SQL Window; or, go down/up a row in the History window and press the "Ctrl+Up" or Ctrl+dwn" key.

How to increase Linux Display/Screen size?

While in Linux, under System Menu, Click on "Preferences", then select "Screen resolution" (Screen1). Change the resolution to the size you would to increase it to (Screen2).

Screen-1

Screen-2

How to add SQLDEVELOPER to Linux Start Menu

How to add SQLDEVELOPER to Linux -GNOME- programs /start Menu? Well, I liked to have a shortcut to SQLDEVELOPER added to Linux Start Menu, similar to Windows  Programs Menu automatically. Since SQLDEVELOPER does not do that, we need to manually add an entry to the programs folder. (By the way, this procedure can be used to add any executable or shell program to the linux menu).

I have enclosed below screenshots to help understand the procedure.See

Screen-1

Click on New Item (Screen 2)

Screen-2

Third, Click on the Browse Button (Screen 3)

Screen-3

Fourth, navigate to the directory where SQLDEVELOPER.sh is kept (Remember to click on sqldeveloper.sh and not on exe; usually it will be located at $ORACLE_HOME/sqldeveloper and select sqldeveloper.sh (Screen -4)

Screen-4

This will bring you back to Screen 3. Now Click on "No Icon" button.  (Screen-5)

Screen-5

 Navigate to $ORACLE_HOME/sqldeveloper/sqldeveloper/bin and select splash.png (Screen-6)

Screen-6

Click OK, you will the program appear in the menu. (Screen-7)

Screen-7

When you click on the program you will see a screen like the one below (Screen-8)

Screen-8

Once launched, SQLDEVELOPER should look like the screen below (Screen-9)

Screen-9

Note: Since I have 11g installed and 11g comes with SQLDEVELOPER, I need to locate the latest SQLDEVELOPER. Used locate command to determine the path (see below). The first one is latest version.

Screen-10

Update: This has been published at Oracle SQLDEVELOPER tips & tricks as well Click here to goto SQLDEVELOPER Exchange

Linux.com :: Disk usage analysis and cleanup tools

Linux.com :: Disk usage analysis and cleanup tools

Excellent tool to analyze file sizes in Linux OS. I used to find Disk Usage using du utility, but after using baobab I simply love it. For more information click on the hyperlink above.
Open a terminal window (equivalent to command window in Windows) and type baobob. It will launch a window displaying disk usage of the directory or the total disk, depending on whether you are at root or in one of the branches. You can simply double click on the folder to drill down or use wild card searches.
I have enclosed a screenshot of baobab above. Navigation: Applications -->System Tools --> Disk Usage Analyzer. Or of course, you can launch from the command prompt window by typing baobab

List of commands I frequently use in Oracle

Listed below commands I fequently use on Oracle in Linux OS environment.
(I will keep updating as I come across more)...
Oracle Commands:

• .How to find whether listener is running or not? 
• lsnrctl status
• to start listener 
• lsnrctl start
• to stop listener
• lsnrctl stop 
• to list services
• lsnrctl services
  
• To Configure Listener
• from command prompt type netca
• to start dbconsole (Enterprise Manager Console)
• emctl start dbconsole
• to stop dbconsole
• emctl stop dbconsole
• to access Enterprise Manager
• https://<service_name>:1158/
• for example if your service name is my.example.com then access url will be https://my.example.com:1158/
• How to start Oracle dB?
• sqlplus /nolog
• sql> connect / as sysdba
• startup
• How to shutdown Oracle dB?
• shutdown immediate
• How to lock a user account & of course to unlock?  
• SQL> ALTER USER <username>  ACCOUNT LOCK;
• SQL> ALTER USER <username> ACCOUNT UNLOCK;
• If you want to change the password while you unlock, use the following command: 
• SQL> ALTER  USER <username> IDENTIFIED BY <password> ACCOUNT UNLOCK;

List of Commands I use frequently in Linux/Unix

Being a developer, I hardly ever use Unix/Linux. However,every now and then I need to do work on Linux. Instead of keep searching internet or bug my friendly colleagues, I think it is a better idea to list out Linux commands below. So here goes (I will keep updating as I come across more)...

• remove directory /files.
• rm -fr *.*
• f flag will force remove (and not interactively ask whether you need to remove or not)
• r flag will allows for recursively deleting all files and directories
• note: if there is a need to ask before deleting any file, then use i flag
• How to find ip address in Linux?
• ifconfig will print the ip address
• note: if the above command returns "not found", then, use /sbin/ifconfig
• How to find Disk Usage: Link to baobob: Linux Disk usage analysis and cleanup tools

• How to find out where "java" or any other file installed (its complete path)?
• the command whereis java will list the complete path
• How to execute .bash_profile after changes?
• . ./.bash_profile (there should be a space between the first dot and the second one)
• create alias for commands
• alias cls=`clear tput`
• How to count number of files in a directory?
• file . -type f wc -l
• How to display present working directory in the prompt?
• In bash shell, set PS1=`\w` (I also add a colon ":" and a greater than symbol ">" at the end like this: PS1=`\w :>` for further references goto everything.com
• Vi Commands
• How to display filename while working inside vi?
  Type Ctrl+G
• How to display line numbers?
  Press ':' and type set number
• How to display mode we are working on (APPEND or OPEN...)?
  Press ':' and type set showmode
My earlier post on using Unix Find Command 

Using Unix Find Command

Find:
find . -name "wfstatus.sql" -print
the above command will search all directories starting from current directory for any file containing wfstatus.sql.
Problem: find displays an error message for any directory I do not have permissions.
So how do I suppress these messages?
The following command will do the trick:

find . - name "wfstatus.sql " -print 2> /dev/null
will suppress cannot read dir or Permission denied messages and print only if it finds the file.
Output of this command:
/oracle/prodappl/fnd/11.5.0/sql/wfstatus.sql

explanation:
/dev/null is a virtual file in Unix; data written to is deleted.
I use the cheatsheet from Stanford.edu (to go to stanford clickhere )

In order to do a case-insensitive search, instead of "name", use "iname":
find . -iname "WFSTAtus.sql" -print 2>/dev/null

if you want the search to be restricted only to files, then use "-type f"
find . -type f -iname "WFSTAtus.sql"   -print 2>/dev/null
I have posted a list of commands that I use frequently in Linux. List of Commands I use frequently in Linux