1. Using Unix command how to display no of records in oracle?

>wc -l filename

Example:cat>file
1 abc 100
2 def 200
3 ghi 300
4 ijk 500

>wc -l file
4 file

2. How to find multiple string?

Use extended grep command

egrep 'searchstr1 | searchchstr2' file.txt

3. How do display only hidden files in Unix?

Hidden files will start a period (.) in their names. To
list them use -a option of ls command.

like, ls -ltra

4. How to know the ip address of user system?

nslookup <host_name>
e.g: nslookup ibm6

5. How to list all the hidden files?

ls -ald (In solaris)

ls - ltra (In unix)

6. What is a "parameter card" and what is useful for?

parateter card is a type of card used to provide voice
digital communication to radio stations for therir FMs

7. What is difference between SSH V1 and SSH V2? What are drawbacks of SSH V2?

V1: less secure ,
lacks a strong mechanism for ensuring the
integrity of the connection.
if machine name user ogged in from is present in one of the
follwing file then connection is established.
$HOME/.rhosts, $HOME/.shosts, /etc/hosts.equiv, or
/etc/shosts.equiv,
V2:More secure
provides additional mechanisms for confidential-
ity

8. What are the general Commands in using Unix OS for a beginner?

cat command:used to create and displaying the information
present in the files.
Syntax for file creation: cat>(filename)
Syntax for displaying information in those file: cat
(filename)
Syntax for Appending data in that files: cat>>(filename)
ls command: to list the files present in the system.
ls :will list all the files present in that directory.
ls -l:for long listing of the files.
ls -a:to view hidden files.
ls -ld:to get the permission for the current directory.
ls -ltr:to get the latest file in the directory.
man command:to know more information about the cmds.
Syntax:man <cmd>
eg:man ls
touch: is also used to create the multiple empty files at a
time.
Syntax:touch f{1..10}:creates 10 empty files with names
f1,...f10.
pwd:is used to know present working directory.
cd f1 :to changed to the directory f1.
mkdir <direcoty name>:to create new directory.
rmdir <directory name>:to remove directory when it is empty
only.
rm <filename>:to remove the files.
rm -r <direcotry name>:to remove the files in that
directory recursively.
rm -f <directoryname>:to remove the files in that directory
forcebily.
cp <source> <destination>: to copy the contents of one file
to another
cp -rR <s> <d>:will copy the contents of one directory to
another.
mv <s> <d>:will move the contents of one file to another.
ls -l|grep ^d:toget the list of directories.
ls -i|grep ^_:to get the list of files.
clear-used to clear the screen

10. What is the difference between NFS 3 and NFS 4? What are new features added in NFS4?

nfsv3 acces through udp protocol whereas nfsv4 acces through
TCP/IP protocol

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11. What will be the result if we run the command #find /tmp -mtime -2 and #find /tmp -mtime +2?

find /tmp -mtime n where n can be +ve or -ve

+n says, file modified in last n days
-n says, file modified more than n days ago

ex. if today is 5th of a month

file1 has mtime 3rd
file2 has mtime 2nd

then find . -mtime 2 will report file1
then find . -mtime -2 will report file2 only

12. Suppose i have one column with data smith
john
michale
the o/p should be smith,john, michale how we do in unix?

Suppose they are asking for displaying just one of the
columns in a directory, make a note of that column number
as it appears when we do a ls -lrt. Then we can use awk to
just display the one columns as o/p.

If column number is n, then do this:

ls -lrt | awk '{print $n}'

13. What is grep|sort give example?

grep stands as Globally Search for Regular Expression
and Print.
It is used for displaying the pattern matching lines from
requested file or files .

14. How to move a background job to forward?

./test.pl&
jobs -- get job id of the above process
[3] Running ./test.pl &
fg 3

15. Explain command to display different lines that are found when compare two files?

diff file1 file2

Above command will display all the lines which r diff in
file1 & file2 whereas, cmp will only display 1st occurance
of difference.

16. Explain command to show the space allocation of files?

df -h----- it shows the space alocation for oracle dsata file.
olny for space alocation execute command ll -lrth.

17. Explain command to view process running?

use ps command "process status". I will use "ps -ef" to
list every process in detail.