Complete Unix Commands

1 MADHAV K 

2 MADHAV K  UNIX COMMANDS 

1. $ LOGNAME

: It displays the current user information

2. $PWD

: present working directory

3. $DATE

: It displays the system date & time

4. $clear

: To clear the screen

. $cal

: it current month and year

!. $cal 2000

: "isplays the 2### year calendar

. $cal 8 2006

: displays the %th month of 2##!

%. $exit or logout

: eit from current user account

'. $ who

: displays the all user in who w ho are currently working on ser(er

1#. $i!ger more information

: displays the all user who are currently working on ser(er with

11. Who a" #

: displays current user information

12. Which or where

: displays the location of the gi(en command

)y *ommands:

Du %& ile!a"e ' to find the si+e of one file "u ,sk test.tt

Du %& ile!a"e( ile!a"e2 ). ' to find si+e of multiple files "u ,sk test.tt test2.tt

Du a

*Director+ !a"e,  : -i(e the si+e of all files in that directory.

"u ,sk  also can /e used to find si+e of all the files.

Du a *#! -ou!, ' #t Li%t %i/e o all ile%1oler %i/e i! re%e!t irector+ Du 34a&hr%tx5' "u for folder can /e used with any of these characters 0ut I am getting same result for "u ,tr

Du h *#! -ou!, ' co!%ier %i/e o irector+ while calcualati!g

3 MADHAV K 

E:files in dsdu 5h 120 .6In 0ound6testing789I 14.#;0 .6In 0ound 13.#;0 .6
ow to i! all the ile% i! all the irectorie% i! that oler7 uo%e 1ile% i! D% i% the oler which ha% %o "a!+ ile% a! al%o 2 1oler% #! -ou! a! Out -ou!. We wa!t the ile% re%e!t i! #! -ou! a! al%o Out 9ou!: #! that ca%e what !ee% to 9e u%e7 L% ; 

=yn: $which pwd 13.
: is use to create new files or to open eiting files or to append

d

;eirect' cat file1 file2 file3 file455555555reirect outut Ae!: cat filename55555555 %i!gle ile files

$cat file1 file2 file3 ?)@555555"ulti

55555555555 55555555555cntl>d

Oe! ile' cat =ile!a"e33333 "ulti files

oe! %i!gle file

$cat file1A file2A file35555555555to oe!

4 MADHAV K 

*at .filename555555555for hie! files 14. Touch

: It is used to create an empty file i.e. # /yte file

=B9: $ touch filename $ touch file1 file2 file3555555555 create multiple files 1. r"

: deleting files or directories ? rm filename5555555555555555deleting single file rm 5i filename55555555555555deleting files with confirmation rm file1 file25555555555555555deleting multiple files rmdir dirname55555555555555deleting the directory /ut the directory must /e empty rm 5r dirname5555555555555deleting directory recursi(ely Ci.e. with tree strD rm ,ri dirname5555555555555remo(e directory with confirmation rm 

555555555555555555555 it delets all files

rm 5I 55555555555555555555delets all files with confirmation rm t 555555555555555555555it delets whose file name starts with EtF  Gow to delete the directory which is not emptyH ?: m ,r Testing78ni. 1!. "&ir

 : creating directories

=yn: $mkdir dirname =ys: $)kdir .dirname555555555555hidden directory 1. <

: change directory =ys: $cd a/c $pwd5555556home6madha(6a/c using a/o(e cmd we can come out from a/c now we at 66home6madha( cd..555555555555555555555555555to come out from current directory cd..6..555555555555555555555555parent directory cd6555555555555555555555555555it changes to root directory

5 MADHAV K 

cd J5555555555555555555555555it changes to home directory

1%. c

:copy source file to target file

? *p emp1 emp25555555555555555555555emp1 tp 2 coping *p ,I m1 m25555555555555555555555555o(erwrite confirmationH B *p , source directory to target directory5555555cp , a/c y+ 1'. ">

: it is used to rename or mo(e file

?: m( eiting filename new filename )( emp .emp5555555555555555555555to hide )( .emp emp55555555555555555555to unhide 2#.l%

: displayA list of all files & directories in a current directory

21.l%?"ore

: displayA list of all files & directories page /y page

22. l% a : displayA list of all files & directories including hidden files and dirctories also in current directory 23. l% r

: display list of all files & directories re(ers order in a current directory

24. L% ; 

: display list of all files & directories recursi(ely in a current directory

2. L% t current directory

 : display list of all files & directories according to date of cr eation in a

2!. L% 1 directory

 : display all list of files & directoriesA link filesA .ee files in a current

2. L%3x current directory

: display all list of files & directories according to width wise in a

2%. L%3L i.e. ' fields

: display all list of files & directories in a current directory in a long list

(@ 1ile t+e%

6 MADHAV K 

1D 55 Kor regular file iiD dLfor dir file IIID MLfor link file IN @ /Lfor /lock of filesND cL for char files here INA N is e>ice ile%5 2D Kile permissions 3D no. of links 4D owner name D group name !D file si+e in /ytes D "ate %D time 'D filename

3#. c"

: it compares two files char /y char

=ys: cmp file1 file2 ?:files in dsIn 0oundcmp type1.tt type2.tt type1.tt type2.tt differ

r: char 2A line 2

?: a1: Gello -ood )orning a2: Gello -ood ?(ening If two lines are same then return nothing If two files are are different then it displays line num/er with character position 31. co"".

: It display common lines /6w 2 files

=yn: *omm Kile1 file2 32. i  33. g

: it display different lines /6w 2 files : it display the file contents page /y page =yn: $@g filename

34. "ore

: it also display the file contents page /y page =yn: $more filename

34. hea

:it display the 1st n lines from the file =ys: $ head ,n filename

3. tail

: it display the last n lines fr om file =yn: tail ,n filename

Tail >n filename5555it indicates nth line to end of the line ?: tail >3# file Cin this file total no of records is 1##D it displays the records from 3# th to 1## 3!. wc

: it counts the no of linesA wordsA chars in a gi(en file.

7 MADHAV K 

=yn: $wc filename iD wc ,l filename555555555555555555it gi(es the no of lines in a gi(en file iiD wc ,w filename555555555555555it gi(es the no of words in a gi(en file IIID wc ,c filename555555555555555 it gi(es no. of char in file i(D wc 5lw filename55555555555555 it gi(es the no of lines and character in a gi(en file

3. OIM" *P" *GP*T?= or )?TP *GP*T?= iD

EF55555555it matches E#F or more chars

iiD EHF 5555555it matches any single chars iiiD 

 555it matches any single chars in the gi(en list

i(D E,E555555it matches any single char in the gi(en range 1D ls t555555555555555it list the files starts with EtF  2D ls s 5555555555555it list the files that ends with E=F 

3D ls /k55555555555555it list the files starts with E/F and ends with EkF  4D ls aH55555555555555it list the 2 characters filename 1 st later fallowed /y EaF and second letter is any one character

D ls/knt55555555555it list the files starts with E/F or EkF or EnF or EtF  !D ls a/cdefgh or lsa5h55list the filesA first char /6w EaF to EhF 

D ls /5kp5td5n555555555 it list the files the 1 st character E/F to EkF 2 nd char EpF to EtF  3rd char EdF to EnF after that a ny no of characters ls doesnFt care a/out *ase sensiti(e e: ls aeiou.tt and lsP?I<8.tt /oth will gi(e the same result 3%. gre

: glo/ally search a regular epression and print it

Is used for to search a string or regular epression in a gi(en fileCsD ID ?g: $ grep madha( sample <6p: 2nd line th line

8 MADHAV K 

th line iiD ?g: $grep madha( a1A a2A a3:  

a1:555555

 

a2:555555 a3:555555 iiiD $ grep techno 555555it searches for techno in current dir files Call filesD i(D $grep techno soft sample55555it searches for more than one wor d Oe kept it in Q

Q

(D $grep Qtechno softR sample

gre c" otio!% $ grep ,i techno sample55555555555555555555555ignore case sensiti(e $ grep ,c techno sample55555555555555555555555count no of lines $grep ,n techno sample55555555555555555555555print along with the line num/ers $grep ,l techno 555555555555555555555555555555list only file names $grep ,( Qtechno softR sample555555555555555not matches print the lines $grep ,ci techno sample5555555555555555555555Ignore case sensiti(e found no of lines $grep Qtechno R sample555555555555555555555pattern

;egular exre%%io!' any string contains wildcard charctor knows as regular epression or pattern These patterns are of   t+e%:


Wor atter! :6S

6

6S 5555555start of the word  6555555end of the word

9 MADHAV K 

-rep Q6Stechno6R sample 555555555555o6p: techno -rep Q6StechnoR sample5555555555555555o6p: techno soft  

55555555555555555o6p: techno 123

-rep Qtechno6R sample

5555o6p: hellotechnoA a/ctechno

-rep Q6S #5'#5'#5'#5'6R sample55555555555555it display 4 digits Ci.e.1234A 4!D

Li!e atter!' B3333333333 starts of the file $5555555555ends of the file ?: grep QdR sample555555555555555it display the line starts withEdF  -rep QtheR sample55555555555555555it list the lines start with EtheF  -rep Q6Sthe6R simple 5555555555sample the line eactly start with EtheF  -rep Qt$R simple5555555555555555555list the line ends withEtF or last char isEt2#1' -rep Q#5' $R sample555555555555 display the line ends with # to ' digit -rep Q /ktR sample555555555555list the line starting with E/F or Ek EorF tF  -rep Q /ktR sample5555555555list the line which is not start with E/F or EkF orEtF  -rep QR89I$R sample 555555555display the line ha(ing only word E8niF  -rep QU. $R5555555555555555555555list the line which contains E4F characters C.D5555555555555555555555555555555555represent single charctor -rep Q.R555555555555555555555555=ample it list all lines -rep Q6.R =ample: 55555555555555it lists the line start with C.D Oe use  to search A $A  as a charctor5555555 i.e.AVA$ -rep Q$R sample55555555555555 it list empty lines -rep ,c Q$R sample5555555555counts no of empty lines in a file -rep ,( Q$R sample5555555555print not matches Ci.e. not emptyD lines -rep ,( Q$Rsample temp

10 MADHAV K 

)( temp sample5555555555555555555here /oth are delete empty files This command is used to show the Pfter 3 lines when the string is found -rep ,P 3 ,i Q*handraR emp.tt This command is used to show the 0efore 3 lines when the string is found -rep ,0 3 ,I QseR emp.tt If the no.of lines found are not eactly same as the lines found then it will result the lines that it found.

3'. gre epression

: it is used for search multiple strings /ut it doesnFt allow to search regular

$grep Qhello    

techno 89IRsample5555555555it searches for hello or techno str 89I

4#. egre

: it is com/ination of grep and fgrep

$egrep Qhello   hello 89IRsample 41. e

$egrep Q$R sample

: to replace a string

$ sed Qs6eisting string6new string6gR filename55sed is used to find and replace and grep is for find print Gere g is to state that replace eisting string with new string -lo/ally. If we want to replace only second instance then =ed Qs6 eisting string6new string62R  Oe can use any delimiter to replace the command =ed QsV eisting stringV new string VgR  Oe can replace the string in only one particular line =ed Q3 sV eisting stringV new string VgR 

11 MADHAV K 

Oe can replace range of lines /y using /elow command =ed Q1A3 sV eisting stringV new string VgR 

Oe can find any no.of lines 2 times /y using sed command =ed EpF emp.tt 5 This will print all lines 2 times Oe can print only particular lines of a file =ed ,n E1pW$pF emp.tt Oe can delete lines /y usin sed =ed E2 dF emp.tt

"elete

=ed E1dW $d E emp.tt =ed E1A dF emp.tt

2 line

"elete

"elete

1 and last line

the line range from 1 to .

iD $sed Qs68ni6Minu6gi Qmadha(: 5555555555555 Ei Efor case sensiti(e iiD $sed Qs68ni6Minu6giR5555555555555555555555 whate(er lines starting with 89I are replaced /y Minu iiiD $sed Qs6$6I like 8ni6g IR sample55555555empty string are filled with EI like 89IFF  i(D $=ed Qs68ni66g IR sample55555555555555555it search 89I if found replace w ith EnothingF CemptyD 42. tr

: to translate a charctor iD tr QaR QpR Ss55555555555555555555 it read data from sample and EaF is replaced /y EpF  iiD tr QaeiouR QP?I<8RSsample5555replace char /y char iiiD tr QAR QltR Semp5555555555555555whene(er QAR is there replace with ta/ space i(D tr Qa5+R QP5X S=i(a55555555 con(erts hole file into uppercase

43D
: it is used for to retrie(e reYuired fields and characters from a gi(en file

12 MADHAV K 

?: madha( is good /oy55 1% chars *ut ,f 25 madha(555 o6p: adha *ut ,c 151# madha( *ut ,c 51#A 152# madha(5555555 for e(ery line 51#A 152# characters *ut ,c 1A2A3 emp.tt

@rints

*ut ,c 153A45! emp.tt *ut ,c1#5 emp.tt

1A2 and 3rd char of each line

 prints

@rint

1 to 3 and 4 to ! character of each line

the lines from 1# th to end position /y using cut

command Oe can print the lines /y using delimiter *ut ,dFAF ,f2 emp.tt

This

will print the 2nd word of each line /y taking EAF as

delimiter. *ut ,dFAF ,f2A3A emp.tt

This

will print the 2nd and 3rd words of each line /y

taking comma as delimiter.

Gow to get the last field of a file. *at emp.ttV re(V cut ,dFAF ,f2 Vre(

44D Pa%te

: is used for to Zoin two or more files hori+ontally /y using delimiter

*at states filename

cat cities

paste ,d Q:Rstates citiestr

P@

Gydera/ad

P@: Gydera/ad

Tamilnadu

madras

Tamilnadu: madras

;arnataka

0angalore

;arnataka: 0angalore

;erala

Tri(andrum

)aharashtra

0om/ay

4D ort : it is used for to sort the file content. 0y default it sorts file contents /ased on P=*II (alues5default is ascending =ort sample iD sort ,r sample555555displays descending order

13 MADHAV K 

iiD sort ,u sample55555it displays uniYue lines in the gi(en file iiiD sort ,n file5555F9R numeric comparisons i(D sort ,nur file (D sort sample temp $m( temp sample

orti!g the ata iel 9+ iel >pos55starting field 5@os55ending field CoptionalD iD =ort ,f >pas1 ,pas2 filename iiD =ort ,f >1 53 filename55555starting from end /efore 3 iiiD =ort ,fn >2 53 file 555555it gi(es only num/ers 4!D C!i order

: it displays uniYue lines in the gi(en file /ut the file contents should /e in sort

?:file1

iD $ uniY file

iiD $uniY ,u filename55 it eliminates duplicates

Paaaaa Paaaaa

Paaaaa

ccccc

Paaaaa

cccccccc

ddddd

*cccccc

dddddd

@pppp

"dddd

hhhhhh

ttttttt

Ghhhh

pppppp

Ghhhh

ttttttttt

@pppp Ttttttt iiiD $ 8niY ,d filename5555displays only duplicated lines

IND uniY ,c filename55555it counts

how many times lines duplicated

   

Paaaaa555552 *ccccccc55551

14 MADHAV K 

ND $ uniY ,u file temp $ m( temp filename "elete duplicated lines from file

"dddd555551 Ghhhhh5552 @pppp555551 Ttttttt555551

4Dii!g?@ : it is used for to com/ine 2 or more cmds Vtake left side o6p to right side cmd as i6p iD $who Vwc ,l555555555count total no of lines CfilesD in c urrent directory iiD $ lsVwc ,l555555555555displays total no of su/directories in the current directory iiiD ls ,l Vgrep QdR5555displays total no of su/directories who stats with line noEdF  iND $head 53# sampleVtail >2# sample555555display the the lines from 2# to 3# from gi(en file (D $ grep 89I stud V cut ,f 2A 3Vsort filename 55555 display 89I students names & ph no in ascending order 4%@ $tee

: it is used to for to write data to the file as well as to the screen $grep 89I stud V cut ,f 2A 3 Vsort Vtee file1

F@ hell %criti!g' It is group of 89I commands and shell keywords The main concept of shell scripting is to handle tet files ID -ou!e %hell 5555stea(e 0ourne 55555$55555555sh555 Csh as i!terreter@ ii@ -a%h %hell C/orne again shellD 555same as a/o(e55ad(anced (ersion of 0ourne is 0P=G CMinu default shellD iii@ Hor! %hell555555"a(id korn5555$5555555555ksh CinterpreterD 5555used as PI default shell )ostly used shell is korn shell it supports re usa/ilityA all shell designed on /ourn shell #@ $&%h

I(D $echo $0 I2@ $alia%

: shift to korn shell : it displays current child shell name : it lists all alias names

15 MADHAV K 

I@ C!alia% alia% !a"e%' to delete alias names : it displays the pre(iously eecuted commands

IF@ $ hi%tor+

: it display the string on scree n CmonitorD

II@ Echo

1ile er"i%%io!%'xxxxxxxxx@ C%erow!er333er"i%%io!%

ir%t art@

Grou er"i%%io!%

%eco! art@

Other er"i%%io!%

thir art@

J333 a er"i%%io!% to ugo 9ut it oe% !ot elete exiti!g er"i%%io!@ 333 e!+ er"i%%io!%@ K3333 a%%ig! er"i%%io!% a er"i%%io!% to ugo 9ut it elete exiti!g er"i%%io!@@ rw56rw56r55 555555555"efault permissions for regular files rw6rw6r5555555555default permission for directories !D ch"o

: it is used for to change file permissions

=yn: $chmod who6 >656[6 iD ls ,l filename5555555rw5 rw5

rL

iiD chmod g> filename55555rw5 rw rL iiiD chmod u>A g5w filename555555rw r5 rL iND chmod g[w filename55555rw ,w5 rL

Octal coe ;ea333333F Write333332 Execute( $chmod ! filename5555555rw r5 rw5 $chmod !42 filename5555 rw5 r55 5w5 D chow!

: to change owner name of the file

\chown owner name filename

16 MADHAV K 

%@ chgre

: to change group name of the file

\ chgrp group name filename %@ $write ser(er

 : it is user for to with the users /ut the user should /e logged into the

$write techno2 Gello

iiD $mesg n55deny the msg iiiD mesg y5to allow msges

*mtl>d 'D aw&!aw& file

: scan for patterns in a file and process the results

!#@ cat

: concatenate ClistD or file

!1D ch%h Cpaawd ,e65sD userlogin7shell: change the user login shell !2D  

: report the summary of disk /locks and nodes free and in use iD df ,k555it displays the disk space in /ytes iiD df ,h555it displays disk space in kilo /ytes iiiD df ,g555it displays the disk space in giga /ytes

!3Du :it displays the directory wise disk usage in form of /locks each /lock si+e is 12 /ytes !4Dg /i

:to create a +ip file

? $g+ip filename5555 o6p: filename.g+ To *reate multiple Xip files to a single Xip file we use /elow command Xip my+ip.+ip emp.tt The a/o(e command will +ip all the files to )y+ip.+ip and we c an get all files starting with emp. !D gu!/i

: to un+ip the files

?: gun+ip filename.g+ !!. co"re%%

: it also used for to +ip the file555 it used to sa(e with .+ format

!D C!co"re%%

: same as a/o(e

-+ip sa(es more memory than compress !%D /cat

: it used to displays +ip file contents in reada/le format

17 MADHAV K 

$+cat sample.g+

c $ sleep 1##&  #D % or $ %   : it displays current user account running process list Cshow status of acti(e processD 1D $% a: it displays all user accounts running process list 2D Hill

: it kill /ackground process

?: kill @I" 3D tel!et

: to connect to remote ser(er

4D t: file transfer protocol 55555transfer files from one ser(er to another $ ftp ipaddress Mogin: 5555555 @assword: 555555 Ktpls Cser(erD KtpVlsCclientD Ktpget filename Cto download a fileD Ktpmget file1 file255555 Cto download multi filesD Ktpput filename Cto upload a fileD Ktpmput file1 file255555 Cto upload multi filesD D1t: to transfer files from one ser(er user account to another ser(er user account $su root 55to switch to admin !D Wall : it is used for to sent /roadcast message to all users who are currently working on ser(er

18 MADHAV K 

$wall Gappy new5year *ntl>d D"ail mail

:it is used for to send the mailA if user is not logged in then also we can send

iD $ mail techno1 *ntl>d e(ery user contains mail/o at a time we can send msg to multiple users 2D $mail techno1 techno2 techno 3 =u/: from techno *ntl>d iiiD $ mail technoSstud stud send content as a mail to techno3 mail is the cmd to read mails in the mail/o $mail 1first mail 2second mail reading &2 it Yuickly opens second mail &Y55Yuit from mail /o &w to sa(e mail contents to a file &pprint mail contents &r55replays &d5delete mails %@$"ail  :to read mails send to secondary mail/o 'D e"ac%

:full screen editor

%#@ echo

: echo the tet string to on monitor

%1D ile

: classify the file type

19 MADHAV K 

%2D exr

: e(aluates the argumentsA used to do arithmeticAetc in the shell

%3D i!

: find filesA matching a type or pattern

%4D o%t!a"e

: display or set the name of the current machine

%Dl!

: link the source to target

%!Dl Al%tat

:show the status of the print Zo/s

%Dlr:l

:print to defind printer

%%D lr": ca!cel

: remo(e a print Zo/ from the print Yuee

%'D "a!

:display manual of gi(en cmd

0@o

:octal dump a /inary fileAin octalAP=*IIAheAdecimal or char

'1Da%%w

:to set or change password

'2D r

: filter the file and print it on the terminal

'3D rc ho%t!a"e

: remotely copy files from this machine to another machine

'4D rlogi!e ho%t!a"e: login remotely to another machine 'D r%h ho%t!a"e

: remote shell to run on another machine

'!D %crit ile eecuted

: sa(es e(erything that appears on the screen to file until eit is

'D %ource ile

: read cmds from the file and eecute them in the current shell

'%D %tri!g ile

: used to search /inary files for P=*II strings

''D t+

: set or display terminal control options

1##D uuecoe ile

: decode a uuencoded fileA recreating the original file

1#1D uue!coe !ew !a"e : encode the /inary file to 5/it P=*IIAusefull when sending (ia emailA to /e "ecode as new name at destination 1#2D >i

: (isual Afull screen editor

1#3D o9%

: display /ackground and suspended processes

1#4@ &ill (

: remo(e suspended process \1

1#D to

: display the currentA most computer5intensi(e commands

1#!D o%>iew

: display the operating system statistics

1#D %ete!>

: list en(ironmental (aria/les

20 MADHAV K 

CN#

What i% "ea!t 9+ a%%w ile7 This file maintains each and e(ery user information with  fields. The  fields are 8sername: passwd: uid: gid: fullname: home: shell.

What i% hell7 =hell is a command line interpreter. =hell acts as an interface /etween user and the kernel.

What i% Her!el7 ;ernel is core part of 89I o6s. It is a group of hundreds of system calls.

What are iere!t la>or% o C!ix o%7 Pny operating system designed /ased on uni kernel called as fla(our of uni. The following are some fla(ours of uni Minu 5555 ed Gat =un solaris 555 =un )icrosystem I0)5PI 55555 I0) Gp5u 55555 G@ =co5uni 55555 santa crus operations II555555 =ilicon -raphics.

What are the iere!t %ecurit+ eature% i! C!ix7

1. @assword protection. 2. Kile permissions. 3. ?ncryption.

What,% the co""a! to i! out toa+,% ate7 date

What,% the co""a! to i! out u%er% o! the %+%te"7

21 MADHAV K 

 who

ow o +ou i! out the curre!t irector+ +ou,re i!7 pwd

What i% the co""a! to %ee the locatio! o co""a!7 Ohere is Scommand name

ow o +ou i! out +our ow! u%er!a"e7 Ohoami

CorD log name

ow to clo%e the curre!t u%er accou!t7 ?it

ow to create e"t+ ile7 Touch Sfilename

ow o +ou re"o>e a ile7 m Sfilename

ow to oi! "ultiile ile% >erticall+7 *at

file1 file2 file3 UU

The ile or which we o !ot ha>e write er"i%%io! ca! 9e elete u%i!g the co""a!7 rm 5f Sfilename

ow o +ou re"o>e a irector+ a! it% %u9irectorie%7  rm ,rf Sdirectoryname

ow to re!a"e a ile7 )( Sfilename

ow to co+ "ultile ile% a! irectorie% i!to %o"e other irector+7 cp 5r source7directory destination7directory ow to %ee hoe! ile%7 Ms ,a

ow to %ee ile% a! %u9irectorie% ile% recur%i>el+7 Ms ,

ow to %ee ile% i! lo!g li%t or"at age wi%e7 Ms ,l V more

ow to ie!ti+ whether a ile i% !or"al ile or irector+7

22 MADHAV K 

$ls 5l filename6directoryname if the first digit is 5 then it is fileA if it is d then it is directory file

What i% the iere!ce 9etwee! l% 3r a! l% 3;7

 ls 5r lists the files in re(erse alpha/etical order... whereas ls 5 lists the files and directories recursi(ely

The iere!ce 9etwee! a %ot li!& a! a har li!&7 P sym/olic CsoftD linked file and the targeted file can /e located on the same or different file system while for a hard link they must /e located on the same file system.

what are the iere!t co""a!% u%e to create ile%7 1.touch 5 to create empty files Ce.gD 5 touch Sfilename 2.(i Sfilename 3. catfilename

Li%t %o"e wil car character%7 H 5 Iit matches any single character  5 It matches +ero or more characters  5 It matches any single character in gi(en list

.3

It matches any single character ecept enter key character

what i% the outut o the ollwi!g co""a! ' l% 4a3"!o3r5Q

list all the files in the current directory starting alpha/et is /etween a to m or n or /etween o to r

ow o +ou cou!t wor%: li!e% a! character% i! a ile7 Oc Sfilename

which co""a! i% u%e to ie!ti+ the t+e o the ile7 file

23 MADHAV K 

gre "ea!% -lo/ally search a regular epression and print it

ow o +ou %earch or a %tri!g i!%ie a gi>e! ile7 grep string filename

ow o +ou %earch or a %tri!g i!%ie a curre!t irector+7 grep string 

ow o +ou %earch or a %tri!g i! a irector+ with the %u9irectorie% recur%e7  grep 5r string 

Diere!ce 9etwee! gre: egre a! gre

grep : does not accept more then one epression

egrep : accepts more than one pattern for search. Plso accepts patterns from a file.

fgrep : accepts multiple patterns /oth from command line and file /ut does not accept regular epressions only strings. It is faster than the other two and should /e used when using fied strings.

What are li!e atter!%7  5 start of the line $ 5 ?nd of the line

ow to %earch e"t+ li!e% i! a gi>e! ile7 -rep Q$R Sfilename

ow to cou!t !o o 9la!& li!e% i! a ile7 -rep ,c Q$R Sfilename

ow to re"o>e E"t+ li!e% or" a gi>e! ile7

24 MADHAV K 

-rep ,( Q$R filename  temfilename )( tempfilename filename

What i% atter! to %earch F igit wor i! a ile7 -rep QS#5' #5' #5' #5'R filename

What i% atter! to %earch the li!e ha>i!g o!l+ three character%7 -rep Q)$R filename

What i% atter! to i%la+ li!e% e!i!g with S$R character i! a gi>e! ile7 -rep Q$$R filename

ow to i%la+ 2 a! F th ile% ro" a gi>e! ile i the eli"etr i% S'R7 *ut ,dR:R ,f 2A4 filename

ow to i%la+ u!iue li!e% ro" a gi>e! ile7 =ort ,u filename

ow to eli"i!ate co"letel+ ulicate li!e% ro" a gi>e! ile7 8niY ,u filename

ow to re"o>e all ulicate li!e% ro" a ile7 8niY ,u filename  tempfilename )( tempfilename filename

ow to elete ShelloR wor ro" a gi>e! ile7 =ed Qs6hello66R filename awk  
 is awk  is

a powful 8ni command. It allows the user to manipulate files that are s tructured as columns of data and


Exa"le'  ^

 _pattern awk  _pattern

`action_ input5file  output5file

meaning: take each line of the input fileW if the line contains the pattern apply the action to the line and write the resulting line to the output5file.

25 MADHAV K 

If the pattern is omittedA the action is applied to all lines:

ow to co"are two ile% are %a"e or !ot7 *mp

ow to i%la+ the ir%t (0 li!e% ro" a ile7 Gead 51# filename

Write a o!e li!e co""a! to co!>ert all the caital letter% o a ile te%t i!to lower ca%e7 cat filename V tr ]P5X] ]a5+]

The ieli!e to li%t the i>e large%t ile% i! the curre!t irector+ i%

 ls 5l V tr 5s _ _ V sort 5t _ _ 5fnr >4 5 V head ,

The ieli!e to i! out the !u"9er o ti"e% the character 7 occur% i! the ile i% tr 5dc _H_ S file V wc 5c

C "elete all the characters ecept ecept H and then make a word count.D

ow to cou!t total !o. o u%er% wor&i!g i! the %+%te"7 Oho V wc ,l

ow to i%la+ the li!e% ro" I to (0 ro" a gi>e! ile7 Gead 51# filename V tail >

what will 9e outut o ollowi!g co""a!7 echo STec!o%otR ? wc c '

What i% the eault u"a%&7 #22

26 MADHAV K 

What i% the eault er"i%%io! or 1ile  Director+ 7 The "efault pri(ileges for file : !44 The default pri(ileges for directory : 

What CN# co""a! will co!trol the eault ile er"i%%io!% whe! ile% are create7 8mask Exlai! the rea: write: a! execute er"i%%io!% o! a CN# irector+. ead allows you to see and list the directory contents. Orite allows you to createA edit and delete files and su/directories in the directory. ?ecute gi(es you the pre(ious read6write permissions plus allows you to change into the directory and eecute programs or shells from the directory.

What i% ch"o: chow! a! chgr7 *hmod : It is used for to change permissions on files *hown : It is used for to change ownership of a file *hgrp : It is used for to change group of the file

# the ow!er oe%!,t ha>e write er"i%%io! o! a ile: 9ut hi%her grou ha%: ca! he%he eit it7  9o. Ge6she can_tA/ecause the owner_s permission o(errides the group_s. To %ee li%t o ile% a! irectorie% :what er"i%%io! reuire7 ead permission

What are P#D%7 They are process I"s gi(en to processes . P @I" can (ary from # to !3.

ow o +ou li%t curre!tl+ ru!!i!g roce%%7 ps

ow o +ou %to a 9ac&grou! roce%%7 kill pid ow o +ou i! out a9out all ru!!i!g roce%%e%7

% 3ag ow o +ou %to all the roce%%e%: excet the %hell wi!ow7 kill # ow o +ou ire a roce%% i! the 9ac&grou!7

27 MADHAV K 

.roce%%3!a"e   What oe% the co""a! &ill 3 $U  o7 kills the last /ackground process

i there i% a roce%% u wa!t to ru! e>e! ater exiti!g the %hell what i% the co""a! u%e7 9ohup

 which co""a! will get execute e>e! ater +ou log out7  9ohup

which %ig!al ca!!ot 9e trae7 kill ,'

ow to reirect %ta!ar error to a ile7 A!%wer 2 filename What oe% the to co""a! i%la+7 top command displays the current ammount of memory occupied /y the currently eecuting processes and the details. In addition to memory usage top command displays cpu usage and process details

What i% the co""a! to %e! "e%%age to all u%er% who are logge i!7 Oall

What i% the co""a! to %e! "ail to other u%er7 )ail username

ow to oe! %eco!ar+ "ail 9ox7 )ail 5f 

What o +ou o i +ou o!Vt wa!t to 9e i!terrute 9+ other u%er%V "e%%age%7

28 MADHAV K 

Pns. mesg n

hell criti!g #!ter>iew ue%tio!%

Diere!ce 9etwee! the outut o echo QQ a! echo Q Q echo  lists all the filenames in the current directory.. echo   lists all the filenames in the current directory twice.

The other wa+ o ru!!i!g %hell %crit aart ro" u%i!g %h co""a! a! ch"o7 ans:5 using b we can run a shell script

1'. Gow do you refer to the arguments passed to a shell scriptH 5 $(: $2 a! %o o!. $0 i% +our %crit !a"e. 2#. OhatFs the conditional statement in shell scriptingH 5 i co!itio!X the! ) i 21. Gow do you do num/er comparison in shell scriptsH 5 5 e: 3!e: 3lt: 3le: 3gt: 3ge 22. Gow do you test for file properties in s hell scriptsH 5 5 % ile!a"e tell% +ou i the ile i% !ot e"t+: 3 ile!a"e tell% +ou whether the argu"e!t i% a ile: a! !ot a irector+: 3 ile!a"e te%t% i the argu"e!t i% a irector+: a! !ot a ile: 3w ile!a"e te%t% or writea9ilit+: 3r ile!a"e te%t% or reaa9ilit+: 3x ile!a"e te%t% or executa9ilit+ 23. Gow do you do 0oolean logic operators in shell scriptingH 5  U te%t% or logical !ot: 3a te%t% or logical a!: a! 3o te%t% or logical or. 24. Gow do you find out the num/er of arguments passed to the s hell scriptH 5 $Y 2. OhatFs a way to do multile(el if5elseFs in shell scriptingH 5 i co!itio!X the! %tate"e!tX eli co!itio!X %tate"e!tX i 2!. Gow do you write a for loop in shellH 5 or >aria9le !a"eX i! li%tX o %tate"e!tX o!e 2. Gow do you write a while loop in shellH 5 while co!itio!X o %tate"e!tX o!e 2%. Gow does a case statement look in shell scriptsH 5 ca%e >aria9leX i! o%%i9le3 >alue3(X@ %tate"e!tXZZ o%%i9le3>alue32X@ %tate"e!tXZZ e%ac 2'. Gow do you read key/oard input in shell scriptsH 5  rea >aria9le3!a"eX 3#. Gow do you define a function in a shell scriptH 5 u!ctio!3!a"e@  Y%o"e coe here retur! X 31. Gow does getopts command workH 5 The parameters to your script can /e passed as 5n 1 5 2#. Inside the scriptA you can iterate through the getopts array as w hile getopts n: optionA and the (aria/le $option contains the (alue of the entered option.

0atch file:

29 MADHAV K 

0atch files allow )=5"<= and )icrosoft Oindows users to create a lists of commands to run in seYuence once the /atch file has /een eecuted. Kor eampleA a /atch file could /e used to run freYuently run commandsA deleting a series of filesA mo(ing filesA etc. P simple /atch file does not reYuire any special programming skills and ca n /e done /y users who ha(e a /asic understanding of )=5"<= commands.

O;A
1.

OGPT I= "PTP < I9K<)PTI<9H

Pns: The )atter that we feed into the *omputer is called "ata or Information.

2.

OGPT I= "PTP0P=?H

Pns: The *ollection of Interrelated "ata is called "ata 0ase.

3.

OGPT I= P "PTP0P=? )P9P-?)?9T =B=T?) C"0)=D @P*;P-?H

Pns: The *ollection of Interrelated "ata and some @rograms to access the "ata is *alled "ata 0ase )anagement =ystem C"0)=D.

4.

OG?9 *P9 O? =PB P "0)= @P*;P-? P= "0)=H

Pns: Kor a system to ualify as ?MPTI<9PM "PTP0P=? )P9P-?)?9T systemA it must use its ?MPTI<9PM facilities to )P9P-? the "PTP0P=?.

.

OGPT I= <"0)=H

Pns:
!.

9P)? =<)? *<""_= 8M?=.

30 MADHAV K 

Pns: "r. ?.K. *odd presented 12 rules that a data/ase must o/ey if it is to /e considered truly relational.
Information ule: Ta/ular epresentation of Information.

cD

-uaranteed Pccess ule: 8niYueness of tuples for guaranteed accessi/ility.

dD )issing Information ule: =ystematic representation of missing information as 98MM Nalues. eD

*omprehensi(e "ata =u/5Manguage ule: M to support "ata definitionA

Niew definitionA "ata manipulationA IntegrityA Puthori+ation and =ecurity.

.

OGPT P? GI?P*GI*PMA 9?TO<;A P9" ?MPTI<9PM "PTP0P=? )<"?M=H

Pns: aD ierarchical Moel'  The Gierarchical )odel was introduced in the Information )anagement =ystem CI)=D de(eloped /y I0) in 1'!%. In this data is organi+ed as a tree structure. ?ach tr ee is made of nodes and /ranches. The nodes of the tree represent the record types and it is a collection of data attri/utes entity at that point. The topmost node in the structure is called the root. 9odes succeeding lower le(els are called children.

/D Networ& Moel' The 9etwork )odelA also called as the *<"=BM data/ase structureA is an impro(ement o(er the Gierarchical modeA in this model concept of parent and child is epanded to ha(e multiple parent5child relationshipsA i.e. any child can /e su/ordinate to many different parents Cor nodesD. "ata is represented /y collection of recordsA and relationships among data are represented /y links. P link is an association /etween precisely two records. )any5to5many relationships can eists /etween the parent and child.

cD ;elatio!al Moel'  The elational "ata/ase )odel eliminates the need

31 MADHAV K 

for eplicit parent5child relationships. In "0)=A data is or gani+ed in two5dimensional ta/les consisting of relationalA i.e. no pointers are maintained /etween ta/les.

%.

OGPT I= "PTP )<"?MI9-H

Pns: "ata )odeling descri/es relationship /etween the data o/Zects. The relationships /etween the collections of data in a system may /e graphically represented using data modeling.

'.

"?KI9? ?9TITBA PTTI08T? P9" ?MPTI<9=GI@.

Pns: ?ntity: Pn ?ntity is a thingA which can /e easily identified. Pn entity is any o/ZectA placeA personA concept or acti(ity a/out which an enterprise records data. Pttri/ute: Pn attri/ute is the property of a gi(en entity. elationship: elationship is an association among entities.

1#.

OGPT I= ?5)<"?MI9-H

Pns: The ?5 modeling techniYue is the Top "own Ppproach. ?ntity relationship is techniYue for analysis and logical modeling of a systemFs data reYuirements. It is the most widely used and has gained acceptance as the ideal data/ase design. It uses three /asic units: entitiesA their attri/utes and the relationship that eists /etween  the entities. It uses a graphical notation for representing these.

11.

OGPT I= 9<)PMIXPTI<9H

Pns: 9ormali+ation is a step5/y5step decomposition of comple records into simple records.

12.

OGPT P? NPI<8= 9<)PM K<)=
Pns: The Kirst 9ormal Korm 19KA The =econd 9ormal Korm

29KA

32 MADHAV K 

The Third 9ormal Korm

39KA

The 0oyce and *odd 9ormal Korm 0* 9K.

13.

OGPT I= "?9<)PMIXPTI<9H

Pns: The intentional introduction of redundancy to a ta/le to impro(e performance is called "?9<)PMIXPTI<9.

14.

OGPT P? 15TI?A 25TI?A 35TI? < 95TI? "PTP0P=? P*GIT?*T8?=H

Pns: 15Tier "ata/ase Prchitecture is /ased on single systemA which acts as /oth ser(er and client. 25Tier Prchitecture is /ased on one ser(er and client. 35Tier Prchitecture is /ased on one ser(er and client out that on client act as a remote system. 95Tier Prchitecture is /ased on 9 no.
1.

OGPT P? P TP0M?A *
Pns: Ta/le: P Ta/le is a data/ase o/Zect that holds your data. It is made up of many columns. ?ach of these columns has a data type associated with it. *olumn: P columnA referred to as an attri/uteA is similar to a field in the file system. ecord: P rowA usually referred to as tupleA is similar to record in the file system.

1!.

OGPT I= "IKK??9*? 0?TO??9 P @<*?"8PM MP9-8P-? P9" P

9<95@<*?"8PM MP9-8P-?H Pns: @rocedural Manguage 9<95@rocedural Manguage

33 MADHAV K 

P program in this implements a step5/y5step algorithm to sol(e the pro/lem. It contains what to do /ut not how to do .

1.OGPT TB@?
1%.

*MP==IKI*PTI<9
Pns: ""M C"ata "efinition ManguageD

"M "ata uerying Mnaguage 

")M C"ata )anipulating ManguageD "*M C"ata *ontrol ManguageD T*MC"ata Transaction ManguageD

*reate Plter "rop Truncate enameA =elect A Insert 8pdate "elete )erge A -rant e(oke A oll/ack *ommit sa(epoint

1'.

OGPT I= "IKK??9*? 0?TO??9 ""M P9" ")M *<))P9"=H

Pns: Kor ""M commands autocommit is <9 implicitly whereas Kor ")M commands autocommit is to /e turned <9 eplicitly.

2#.

OGPT I= "IKK??9*? 0?TO??9 P TP9=P*TI<9 P9" P 8?BH

Pns: P Transaction is unit of some commands where as uery is a single line reYuest for the information from the data/ase.

21.

OGPT I= "IKK??9*? 0?TO??9 T89*PT? P9" "?M?T? *<))P9"=H

34 MADHAV K 

Pns: Truncate *ommand will delete all the rec ords where as "elete *ommand will delete specified or all the re cords depending only on the condition gi(en.

22.

OGPT I= "IKK??9*? 0?TO??9 8@"PT? P9" PMT? *<))P9"=H

Pns: Plter command is used to modify the data/ase o/Zects where as the 8pdate command is used to modify the (alues of a data /ase o/Zects.

23.

OGPT P? *<))P9"=
Pns: -rant and e(oke are the two commands /elong to the "*M *ategory.

24.

OGI*G I= P9 ?KKI*I?9T *<))P9" 5 T89*PT? < "?M?T?H OGBH

Pns: "elete is the efficient command /ecause using this command we can delete only those records that are not rea lly reYuired.

2.

OGPT P? 8M?= K< 9P)I9- P TP0M? < *
Pns: 1D 9ames must /e from 1 to 3# /ytes long. 2D 9ames cannot contain Yuotation marks. 3D 9ames are not case sensiti(e. 4D P name must /egin with an alpha/etic character from your data/ase character set and the characters $ and \.  0ut these characters are discouraged. D P name cannot /e <P*M? res er(ed word. !D P name must /e uniYue across its namespace.
2!.

G
35 MADHAV K 

Pns: P Ta/le can ha(e 1### columns.

2.

OGPT P? "IKK??9T "PTPTB@?= =8@@<T?" 0B =MH

Pns: *har Csi+eDA 9char Csi+eDA Narchar2 Csi+eDA 9(archar2 Csi+eD data types for character (aluesA 9um/er CprecisionA scaleDA 9um/erA 9um/er CnDA KloatA Kloat C/inary precisionD data types for numerical (aluesA "ate data type for date (aluesA MongA aw Csi+eDA Mong awA *lo/A 0lo/A 9clo/A 0file for large o/Zects.

2%.

OGPT I= "IKK??9*? 0?TO??9 M<9- P9" M<0 "PTPTB@?=H

Pns: M<0

M<9-

1D The maimum si+e is 4-0. 2D M<0s Cecept 9*M<0D can /e attri/utes of an o/Zect type. 3D M<0s support random access to data. 4D )ultiple M<0 columns per ta/le or M<0 attri/utes in an o/Zect type. 1D The maimum si+e is 2-0. 2D M<9-s cannot.

3D M<9-s support only

seYuential access. 4D
2'.

OGPT I= "IKK??9*? 0?TO??9 *GP P9" NP*GP2 "PTPTB@?=H

Pns: Narchar2 is similar to *har /ut can store (aria/le no.
36 MADHAV K 

3#. G
Pns: Kor "ate data type oracle allocates  /ytes )emory. "efault "ate Kormat is: ""5)<95BB.

31.

OGPT I= P9-? K< ?P*G "PTPTB@?
Pns: "atatype *har

ange

Narchar2 9um/er

Kloat

M<9-A POA M<9-PO Marge
CM<0FsD 2### /ytes 4### /ytes @recision 1 to 3% =cale 5%4 to 12 @recision 3% decimals
32.

2 -0 4-0

G
Pns: Oe canFt rename a *olumn of a ta/le directly. =o we follow the following steps. To ename a *olumn: aD

Plter the ta/le specifying new column name to /e gi(en and data type.

/D

Then copy the (alues in the column to /e renamed into new column.

cD

drop the old column.

33.

G
Pns: To "ecrease the si+e of a "ata type of a column i.

Truncate the ta/le first.

ii.

Plter the ta/le column whose si+e is to /e decreased using the same

37 MADHAV K 

name and data type /ut new si+e.

34.

OGPT I= P *<9=TPI9TH OGPT P? IT= NPI<8= M?N?M=H

Pns: *onstraint: *onstraints are representators of the column to enforce data entity and consistency.There r two le(els 1D*olumn5le(el constraints 2DTa/le5le(el constraints.

3.

MI=T <8T PMM TG? *<9=TPI9T= =8@@<T?" 0B =M.

Pns: 9ot 9ullA 8niYueA *heckA @rimary ;ey and Koreign ;ey or eferential Integrity.

3!.

OGPT I= "IKK??9*? 0?TO??9 89I8?>9
Pns: 8niYue and 9ot 9ull is a com/ination of two *onstraints that can /e present any num/er of times in a ta/le and canFt /e a referential key to any column of an another ta/le where as @rimary ;ey is single *onstraint that can /e only once for ta/le and can /e a referential key to a column of another ta/le /ecoming a referential integrity.

3.

OGPT I= P *<)@<=IT? @I)PB ;?BH

Pns: P @rimary key created on com/ination of columns is called *omposite @rimary ;ey.

3%.

OGPT I= P *P9"I"PT? *
@<==I0M? @? *<)@<=IT? @I)PB ;?BH Pns: It is a part of composite primary key. )aimum 32 candidate key can /e there in composite primary key.

3'.

G
Pns: P 98MM (alue is something which is una(aila/leA it is neither +ero nor a space and any mathematical calculation with 98MM is always 98MM.

38 MADHAV K 

4#. OGPT I= 98MMH P *<9=TPI9T < "?KP8MT NPM8?H Pns: It is a default (alue.

41. OGPT I= "?KP8MT NPM8? K< ?N?B *
42. OGPT I= *?PT?" I)@MI*ITMB K< ?N?B 89I8? P9" @ I)PB ;?B *
43. OGPT P? MI)ITPTI<9=
44. OGPT I= "IKK??9*? 0?TO??9 ?K??9*?= P9" K<?I-9 ;?B *<9=TPI9TH Pns: eferences is used as column le(el key word where as foreign key is used as ta/le le(el constraint.

4. OGPT I= ]<9 "?M?T? *P=*P"?]H Pns: when this key word is included in the definition of a child ta/le then whene(er the records from the parent ta/le is deleted automatically the respecti(e (alues in the child ta/le will /e deleted.

4!. OGPT I= @P?9T5*GIM" < )P=T?5"?TPIM ?MPTI<9=GI@H Pns: P ta/le which references a column of another ta/leCusing eferencesDis called as a child ta/leCdetail ta/leD and a ta/le which is /eing referred is called @arent C)asterD Ta/le .

39 MADHAV K 

4. G
4%. I= <P*M? *P=? =?9=ITIN?H Pns: 9<

4'. G
#. OGPT I= P @=?8"<5*
1. OGPT K< ]<"? 0B] *MP8=? K< P 8?BH Pns: To arrange the Yuery result in a specified
2. OGPT I= ]-<8@ 0B] 8?I?=H Pns: To group the Yuery results /ased on condition.

3. 9P)? =<)? P--?-PT? K89*TI<9=
4. OGPT I= "IKK??9*? 0?TO??9 *<89T CDA *<89T CD K89*TI<9=H Pns: *ount CD will count the s pecified column whereas count CD will

40 MADHAV K 

count total no. of rows in a ta/le.

. OGPT K< 
!. OGPT I= P =8058?BH Pns: P Yuery within a Yuery is called a su/ Yuery where the result of inner Yuery will /e used /y the outer Yuery.

. OGPT P? =M <@?PT<=H Pns: Nalue CDA ef CD is =M operator. C 8sed with
 %. ?@MPI9 ]P9B]A]=<)?]A]PMM]A]?I=T=] <@?PT<=H   Pns: A!+: The Pny Cor itFs synonym =<)?D operator computes the lowest (alue from the set and compares a (alue to each returned /y a su/ Yuery.

All' PMM compares a (alue to e(ery (alue returned /y =M. Exi%t%'  This operator produces a 0<
'. OGPT I= P *<?MPT?" =80 8?BA GD on either of the sidesCleft or rightD /ased on the reYuirement.

!3. OGPT I= "IKK??9*? 0?TO??9 ?8I P9" =?MK 
!4. OGPT P? ]=?T] <@?PT<=H Pns: 89I<9 PMMA89I<9A I9T?=?*T A)I98= are =?T <@?PT<=.

42 MADHAV K 

!. OGPT I= "IKK??9*? 0?TO??9 ]89I<9] P9" ]89I<9 PMM] <@?PT<=H Pns: 89I<9 will return the (alues distinctly whereas 89I<9 PMM will return e(en duplicate (alues.

!!. 9P)? =<)? 98)0?A *GPP*T?A "PT?A *<9N?=I<9A

Date 1u!ctio!%: =ysdateA )onths /etween Cd1A d2DA To7char CdA formatD Mast day CdDA 9et7day CdA dayD.add7monthsCdAnDA ?tract

er%io! 1u!ctio!%'

To7charA To7dateA To7num/er

!. OGPT I= "IKK??9*? 0?TO??9 )P CD P9" -?PT?=T CD K89*TI<9=H Pns: )P is an aggregate function which takes only one column name of a ta/le as parameter whereas -reatest is a general function which can take any num/er of (alues and column names from dual and ta/le respecti(ely.

43 MADHAV K 

!%. OGPT K< 9NM CD K89*TI<9 I=H Pns: 9NM Kunction helps in su/stituting a (alue in place of a 98MM.

!'. OGPT K< "?*<"? CD K89*TI<9 I=H Pns: It is su/stitutes (alue /asis and it actually does an _if5then5else_ test.

#. OGPT I= "IKK??9*? 0?TO??9 TP9=MPT? CD P9" ?@MP*? CD K89*TI<9=H Pns: TranslateCD

is a superset of functionality pro(ided /y eplaceCD.

1. OGPT I= "IKK??9*? 0?TO??9 =80=T CD P9" I9=T CD K89*TI<9=H Pns: =u/strCD will return the specified part of a string whereas

InstrCD return the position of the specified part of the string.

2. OGPT I= P 8MIP9 "PB 98)0?H Pns: It will return count of the no.
3. G
4. G
. OGPT I= "IKK??9*? 0?TO??9 T<7"PT? CD P9" T<7*GP CD *<9N?=I<9 K89*TI<9=H

44 MADHAV K 

Pns: To7date con(erts character date to date format whereas To7char function con(erts date or numerical (alues to characters.

!. OGPT I= P NI?OH G
%. OGPT I= P9 I9MI9? NI?OH Pns: Inline (iew is /asically a su/Yuery with an alias that u can use like a (iew inside a =M statement. It is not a schema o/Zect like =M5o/Zect.

'. G
%#. OGPT K< ]OITG *G?*; <@TI<9] K< P NI?OH Pns: ]OITG *G?*; <@TI<9] clause specifies that inserts and updates r performed through the (iew r not allowed to create rows which the (iew cannot select and therefore allows integrity constraints and data (alidation checks to /e enforced on data /eing inserted or updated.

%1. OGPT I= P9 I9"?H P"NP9TP-?
45 MADHAV K 

access to rows in a ta/le. Pn Inde increases the performance of the data/ase.

%2. OGPT I= P =?8?9*?H @=?8"<5*
%3. OGPT I= P *M8=T?H OG?9 T< 8=? P *M8=T?H G
%4. OGPT I= P =9P@=G
%. OGPT I= P =B9<9B)H Pns: P =ynonym is a data/ase o/Zect that allows you to create alternate names for
%!. OGPT I= "IKK??9*? 0?TO??9 @INPT? P9" @80MI* =B9<9B)H Pns:
46 MADHAV K 

%. OGPT I= "IKK??9*? 0?TO??9 ]=M] P9" ]=M@M8=] *<))P9"=H Pns: =M commands are stored in the /uffer whereas =M@M8= are not.

%%. 9P)? =<)? =M@M8= *<))P9"=H Pns:

"?=* *I0?A =TPTA -?TA =PN?A 6 are =M@M8= *<))P9"=.

%'. OGPT P? ]=M@M8= ?@<TI9-] *<))P9"=H Pns: =@<
'#. OGPT P? =B=T?) P9" <0?*T @INIM?-?=H Pns: *onnect and esource etc are =ystem @ri(ileges. *reate So/ZectA =electA InsertA Plter etc are
'1. OGPT K< "*M *<))P9"= P?H Pns: *ommitA oll/ack are "*M commands.

'2. OGPT K< -P9T *<))P9" OITG ]OITG -P9T <@TI<9]H Pns: QOith -rant
'3. G
47 MADHAV K 

'4. OGPT I= P =*G?)P P9" =*G?)P <0?*T=H Pns: P schema is a collection of logical structures of dataA or schema

o/Zects. P schema is owned /y the data/ase user and has the same name as that of user. ?ach user owns a single schema. =chema o/Zects include following type of o/Zects *lustersA "ata/ase MinksA KunctionsA IndeesA @ackagesA @roceduresA =eYuencesA =ynonymsA Ta/lesA "ata/ase TriggersA Niews.

'. G
'!. OGPT I= P =?==I<9H Pns: The period /etween Mogin and Mogoff on schema.

'. OGPT I= P *MI?9T @<*?==H OGPT I= P =?N? @<*?==H Pns: ref: 12  & P.

'%. G
''. G
1##. G
48 MADHAV K 

=?T =M@<)@T Snew prompt.

1#1. G
1#4. OGPT P? "IKK??9T TB@?=
A!o!+"ou%  Na"e -loc&%

49 MADHAV K 

1#. OGPT P? *<)@<=IT? "PTP TB@?=H Pns: ecordsA Ta/les are two *omposite data types.

1#!. OGPT I= =*<@?
1#. OGPT I= P 9?=T?" 0M<*;H Pns: P /lock within a /lock is called 9ested 0lock.

1#%. OGPT I= P @M6=M ?9-I9?H Pns: The @M6=M engine accepts any (alid @M6=M /lock as inputA eecutes the procedural part of the statements and sends the =M statements to the =M statement eecutor in the
1#'. OGPT I= "?KP8MT NPM8? K< P 98)?I* @M6=M NPIP0M?H Pns: 98MM

11#. OGPT I= "IKK??9*? 0?TO??9 =I)@M? M<<@ P9" P K< M<<@H Pns: =imple reYuires declaration of (aria/les used in it and eit condition /ut Kor Moop doesnFt reYuire this.

111. OGPT I= P *8=<H =T?@= T< 8=? P *8=<H Pns: *ursor is @ri(ate =M area in @M6=M. "eclare the *ursorA
50 MADHAV K 

*lose the *ursor.

112. G
113. OGPT I= P *8=< K< M<<@H Pns: *ursor Kor Moop is shortcut process for ?plicit *ursors /ecause the *ursor is
114. OGPT P? *8=< PTTI08T?=H Pns: ^Kound  

^9otKound

 

^Is
11. OGPT I= 8=?
11!. OGPT I= P9 ?*?@TI<9H G
Nalue7?rror etc.

Xero7"i(ideA

9ot7Mogged7
51 MADHAV K 

11%. G
"?*MP? Seception name ?*?@TI<9W 555555555W 5 5 5 5 5 5 5 5 5W 0?-I9 5 5 5 5 5 5 5 5 5W 5 5 5 5 5 5 5 5 5W PI=? Seception nameW ?*?@TI<9 OG?9 Seception name TG?9 5 5 5 5 5 5 5 5 5W 5 5 5 5 5 5 5 5 5W ?9"W

11'. OGPT I= ]
12#. OGPT I= =*<@?
121. OGPT I= P =805@<-P)H

52 MADHAV K 

Pns: P =80@<-P) I= P @M6=M 0M<*;A OGI*G OIMM 0? I9N<;?" 0B TP;I9@PP)PT?=.

122. OGPT P? "IKK??9T TB@?=
123. G
12. OGPT I= ]I9 <8T] @PP)?T?H Pns: P parameterA which gets (alue into the @rocedure or Kunction and takes the (alue out of the @rocedure or Kunction areaA is called I9 <8T parameter.

12!. "
12. OGPT I= P @P*;P-? P9" @P*;P-? 0<"BH Pns: @ackage is declarati(e part of the functions and proc edures stored in that package and package /ody is the definition part of the functions and procedures of that pac kage.

53 MADHAV K 

12%. OGPT I= P"NP9TP-?
12'. I= IT @<==I0M? T< GPN? P @<*?"8? P9" P K89*TI<9 OITG TG? =P)? 9P)?H Pns: 9< if it is out side a @ackageA B?= if it is within a @ackage.

13#. "
131. OGPT I= P TI--?H G
132. OGPT I= "IKK??9*? 0?TO??9 P TI--? P9" P *<9=TPI9TH Pns: *onstraints are always T8? whereas Triggers are 9
133. OGPT P? "IKK??9T ?N?9T= K< P TI--? P9" TG?I =*<@?=H Pns: InsertA 8pdate or "elete.

54 MADHAV K 

134. OGPT I= "IKK??9*? 0?TO??9 TP0M? M?N?M P9" 
 13. OGPT P? P8T<9<)<8= TI--?=H Pns: =upports to pro(ide *ommit statement in Triggers. Triggers a declared as independent  

Transactions.

13!. OGPT I= P9 ]I9=T?P"
 13. G
13%. OGPT I= ]TP0M? )8TPTI9-] ?<H G
Ta/le name is mutatingA trigger6function may not see it

*ause : P trigger or a user5defined @M6=M function that is referenced in the statement attempted to Yuery or modify a ta/le that was in the middle of /eing modified /y the statement that fired the trigger. Pction : ewrite the trigger or function so it does not read the ta/le.

13'. OG?9 T< 8=? ]:9?O] P9" ]:
55 MADHAV K 

 141. G
142. G
143. G
144. G
14. OGPT I= P TP9=I?9T P9" @?=I=T?9T <0?*TH Pns: The
14!. OGPT I= P *
14. G
14%. OGPT I= P *
56 MADHAV K 

14'. OGPT I= "IKK??9*? 0?TO??9 NPPB P9" 9?=T?" TP0M?H Pns: Narray has a fied si+e. 9ested ta/les can carry any num/er of (alues.

1#. G
11. OGPT I= 8=?
12. OGI*G @P*;P-? I= 8=?" K< KIM? I9@8T6<8T@8T I9 <P*M?H Pns: 8TM7KIM? @ackage is used for Kile input6output in
13. 9P)? =<)? )?TG<"= P9" @<*?"8?=
14. OGPT I= =MH G
1. OGPT I= P9 IT?PT<H 9ame some TB@?=
57 MADHAV K 

Pns: =M Iterators are /asically record groups generated during transactionA which reYuires manipulation of more than one records from one or more ta/les. There are two types Iterators namely 9amed Iterator and @ositional Iterator.

 1!. OGPT P? "IKK??9T =T?@= T< OIT? P "B9P)I* =M @<-P)H Pns: ?g: char c7sYlstring[`Q"?M?T? K<) sailors OG?? ratingRW ??* =M @?@P? readytogo K<) :c7sYlstringW ??* =M ??*8T? readytogoW

1. OGPT I= TP0M? @PTITI<9I9- P9" I9"? @PTITI<9I9-H Pns:
1'. OGPT I= @GB=I*PM )?)<B =T8*T8?
1!#. OGPT I= M<-I*PM )?)<B =T8*T8?
1!1. OGPT I= GAH Pns: P =ystem -lo/al Prea is a group of shared memory allocated /y
58 MADHAV K 

1!2. OGPT I= PGAH Pns: The @rogram -lo/al Prea is a memory /uffer that contains data and control information for a ser(er process. P @-P is created /y
1!3. OGPT I= P9 <P*M? I9=TP9*?H Pns: ?(ery time a data/ase is startedA an =-P is allocated and
1!4. OGPT P? "IKK??9T <P*M? @<*?==?=H Pns: P process is a Qthread of controlR or a mechanism in an operating system that can /e eecute a series of steps. =ome operating systems use terms Zo/s or

task. P process normally has its own pri(ate memory area in which it runs. Pn
1!. OGPT I= "IKK??9*? 0?TO??9 @)<9 P9" =)<9H Pns: =)<9 C=ystem )onitorD performs instance reco(ery at instance of startup. In a multiple instance system Cone that uses the parallel ser(erDA =)<9 of one instance can also perform instance reco(ery other instance that ha(e failed whereas The @)<9 C@rocess )onitorD performs process reco(ery when a user process fails.

1!!. OGPT I= "IKK??9*? 0?TO??9 "PTP0P=? P9" TP0M?=@P*?H Pns: "ata/ase is a physical *omponent Ta/lespace is a Mogical component

1!. OGPT I= <0
59 MADHAV K 

Pns: The "ata 0ase Oriter writes modified /locks from the data/ase /uffer cache to the data files.

1!%. OGPT I= <0
1!'. OGPT I= ?*
1#. OGPT I= P*GIN?H Pns: The Prchi(er CP*GD copies the online redo log files to archi(al storage when they are full. AP*G is acti(e only when a data/aseFs redo log is used P*GIM<- mode.

 11. OGPT I= P =T<?" 8?BH Pns: NI?O

12. OGPT I= 8=? @<*?== P9" =?N? @<*?==H Pns: P 8ser process is created and maintained to eecute the software code of an application program Csuch as @<  @rogramD or an <P*M? tool Csuch as =M  "0PD. The 8ser process also manages the communication with ser(er processes. 8ser processes communication with the ser(er @rocesses through the program interface.

 
60 MADHAV K 

ser(er configuration allows many user processes to share a small num/er of ser(er processesA minimi+ing the utili+ation of a(aila/le system resources.

13. OGPT I= P =?MK ?K??9TIPM I9T?-ITBH Pns: Ta/le related to itself .Koreign key of the ta/le links to primary key of the same ta/le.

14. OGPT I= P ]PI=?] =TPT?)?9TH Pns: It is used to aise ?ceptions.

1. OGPT I= 
62 MADHAV K 

 =ystimestamp : -i(es date and time including fractional seconds in =?N? time +one  current7timestamp: -i(es date and time including fractional seconds in *MI?9T time +one  sysdate: -i(es only date in ser(er time +one  current7date: -i(es only date in client time +one  ?tract : 8sed to retrie(e a particular (alue from the gi(en month 6 year D.

date

C day 6

 to7timestampCdD : *on(erts gi(en date into date & time information with am 6 pm .  d/time+one : -i(es ser(er time +one (alue  Timestamp : "ata type Putomatically stores date and time information with am 6 pm .

select systimestamp A current7timestamp from dualW select sysdateAcurrent7date from dualW select d/time+one from dualW select to7timestampCsysdateD from dualW 2#5Zan5#' !:4%:23 pm select etractCday from sysdateD A  etractCmonth from sysdateDA  etractCyear from sysdateD from dualW

 create ta/le temp Cc1 timestampDW  insert into temp (aluesCsysdateDW  select  from tempW  2#5Zan5#' !:2:23 pm 5555555555555555555555555555555555555555555555555555555555555555555555555555 9ew -eneral Kunctions:  *oalesceCepr1Aepr2Aepr3A.......D 555 @icks the first not null epression result .

63 MADHAV K 

nullif C epr1Aepr2 D 555 If epr1 and epr2 results are same it returns 98MM (alue otherwise it return epr1 result.  9(l2Cepr1Aepr2Aepr3D 555 If epr1 is null it manipulates epr3 Aif epr1 is not null it manipulates epr2.

select coalesceC1## > nullA 12% 5 null > 1###A 12  nullA 22A 234A'%%'D from dualW 55 22

select enameA Zo/A coalesce Ccomm  2A sal  1.D /onus  from empW

select nullifC1##A# 2DA nullifC3##A3#  1##DA nullif C!##A3## > 3##D from dualW 55 null 3## null

select rollA nameA nullifCfeeA2##D from student where course [ _
select enameA Zo/A n(l2CcommAsal > commAsalD net from empW 555555555555555555555555555555555555555555555555555555555555555555555555555 )utiple Inserts: =upports to insert into more than 1 ta/le at a time. 0ut input must /e retrie(ed from eisting ta/le.

?: )ake 3 empty ta/les same as "ept ta/le. *reate ta/le "1 as select  from dept where rownum is nullW *reate ta/le "2 as select  from dept  where rownum is nullW

64 MADHAV K 

*reate ta/le "3 as select  from dept where rownum is nullW

insert into "1 select  from deptW insert into "2 select  from deptW insert into "3 select  from deptW

insert all into "1 (aluesCdeptnoAdnameAlocD into "2 (aluesCdeptnoAdnameAlocD into "3 (aluesCdeptnoAdnameAlocD select  from deptW

*onditional Insert: insert all when Cdeptno S[ 4#D then into "1 (aluesCdeptnoAdnameAlocD when Cdeptno S[ '#D then into "2 (aluesCdeptnoAdnameAlocD else into "3CdnameAlocD (aluesCdnameAlocD select  from deptW

insert all when course [ _
65 MADHAV K 

into stu7d!i (aluesCrollAnameAfeeD when course [ _uni_ then into stu7uni (aluesCrollAnameAfeeD select  from studentW

=tudent

stu7oracle

555555555

555555555555

oll

oll

name

name

course

fee

fee 5555555555555555555555555555555555555555555555555555555555555555555555555555 )erge : 8sed to compare the 2 ta/le contents and makes them eYual. It supports only 8pdate and Insert operations .

merge

*lauses:

into Temp T

into 55 Target

using emp ?

8sing 55 =ource

on C T.empno [ ?.empno D


when matched then update set t.sal [ e.salA t.comm [ e.commA t.deptno [ e.deptnoA t.Zo/ [ e.Zo/A t.mgr [ e.mgr when not matched then