DBMS Introduction to SQL

8/10/2019 DBMS Introduction to SQL

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DBMS ( CS 592)

Introduction to SQL

WEEK 1:

In This Course ou !i"" "e#rn:

B#sic SQL

$d%#nced SQL

&L'SQL Concets

$ roect on *r#c"e usin+ SQL #nd

&L'SQL(With ,B -ront end)

Structured Quer L#n+u#+e ( SQL ) is # co.uter "#n+u#+e /or co..unic#tion !ithd#t#0#se

SQL is # oen "#n+u#+e de%e"oed 0 IBM !hose ru"es h#%e 0een set 0 # st#nd#rds

co..ittee

SQL h#s .#n c##0i"ities 0ut the .ost co..on needs in 0usiness #re to:

3e#d e4istin+ d#t#

Cre#te ne! records ho"din+ d#t#

Ch#n+e e4istin+ d#t#

De"ete d#d#

SQL is not # ro+r#. or # de%e"o.ent en%iron.ent such #s $ccess or ,B SQL is #

ure "#n+u#+e

-rontend so/t!#re inter/#ces !ith the user B#c6end so/t!#re ho"ds d#t# SQL is the

st#nd#rd "#n+u#+e /or the t!o ieces o/ so/t!#re to co..unic#te !ith e#ch other

D#t#: A set of information with some aspect in common.

For example data for employees might include social security numbers:

7 1285;1 n#.e? E."oeeID te? inte+er si@e? 11 di+its ( e4#ct" )

-ie"d >2 n#.e? A#.e-irst te? strin+ si@e? ?8= ch#r#cters


2/45

-ie"d >1 n#.e? n#.eL#st te? strin+ si@e? ?8= ch#r#cters

This .et#d#t# descri0es th#t !e h#%e # set o/ d#t# #0out e."oees th#t is or+#ni@ed

into # t#0"e Within th#t t#0"e !e ho"d three 6inds o/ in/or.#tion #0out e#ch e."oee

their ID nu.0er #nd their /irst #nd "#st n#.e

D#t#0#se: $ d#t#0#se is the d#t# #nd the .et#d#t# in other !ords # d#t#0#se is # set

o/ re"#ted in/or.#tion #s !e"" #s # descrition o/ ho! th#t in/or.#tion is or+#ni@ed $

d#t#0#se /or e."oees !ou"d 0e the .et#d#t# !e ust "oo6ed #t "us the in/or.#tion

descri0ed #0o%e under d#t#

E."oee ID A#.e-irst A#.eL#st

1285;


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A#.in+ 3u"es /or t#0"es #nd co"u.ns

Must 0e+in !ith # "etter

Must 0e 1G8= ch#r#cters "on+

Must cont#in on" $GH #G@ =G9 J #nd >

Must not du"ic#te the n#.e o/ #nother o0ect o!ned 0 the s#.e user

Must not 0e #n *r#c"e ser%er reser%ed !ord

1 C3E$TE

SQLCre#te t#0"e e.( Eno nu.0er(5) En#.e %#rch#r2(2=)

E#dd %#rch#r2(8=)

Eoind d#te)

Constr#ints

1. Not Null, 2. Check

1. Primary key, 2. Unique key

Foreign key

1 SQLCre#te t#0"e e."

Eno nu.0er(5) constr#int enonotnu"" Aot Au""

En#.e %#rch#r2(2=)

E#dd %#rch#r2(8=)

Eoind d#te)

2 SQLCre#te t#0"e e.(

Eno nu.0er(5) constr#int enochec6 Chec6 ( eno 1== )

)

8 SQLCre#te t#0"e e." Eno nu.0er(5) constr#int unieno niFue

)

or

SQLCre#te t#0"e e."

Eno nu.0er(5) En#.e %#rch#r2(2=)

E#dd %#rch#r2(8=) Eoind d#te constr#int unieno niFue(eno))

SQLCre#te t#0"e e."

Eno nu.0er(5) constr#int eno &ri.#r 6e

)

or

SQLCre#te t#0"e e."

Eno nu.0er(5)

En#.e %#rch#r2(2=)

sercre#ted

Co"u.n n#.e


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E#dd %#rch#r2(8=)

Eoind d#te constr#int eno &ri.#r 6e( eno))

5 SQLCre#te t#0"e e.1(

#no number"$% constr#int /6eno re/erences e.(eno),

#&type char"'%,

#&salary number"(,'%%)

*r

SQLCre#te t#0"e e.1(

#no number"$%,

#&type char"'%,

#&salary number"(,'%,constr#int /6eno /orei+n 6e(eno) re/erences e.(eno))

2 $LTE3

Adding columns in an exiting table.

1 S*+$"ter t#0"e e. #dd ( Eincode ch#r() E te"ehone ch#r(;) )

Modifying columns in an exiting table.

2 S*+$"ter t#0"e e. .odi/ ( Eno nu.0er() E#dd %#rch#r2(2=) )

-o add onstraints after creating a table.

8 SQL $"ter t#0"e e. #dd constr#int enochec6 Chec6 ( eno 1== ))

SQL $"ter t#0"e e. #dd constr#int eno &ri.#r 6e (eno)

5 SQL $"ter t#0"e e. #dd constr#int unieno niFue (eno)

SQL $"ter t#0"e e.1 #dd constr#int /6eno /orei+n 6e(eno)

re/erences e.(eno)%)

/nly for 0ot 0ull constraint it will be

; SQL $"ter t#0"e e. .odi/ eno constr#int enonotnu"" Aot Au""

For delete the constraints


5/45

$SSIAMEAT1

1ou should create the following table with your class roll number li2e emp&'3 where class roll number 4 '3.

5. reate table #M6 with the following structure.

'. 7isplay the structure of #M6 table.

3. Modify the #M6 table add a new column named !7#6-0/8 with data type integer

9. reate table 7#6- with the following structure.

$. Modify the #M6 table add referential integrity on !7#6-0/8 with the parent 2ey 7#6-"7eptno%.

. Modify the 7#6- table delete column !ity8.

;. Modify the #M6 table delete the constraint from s#".

(. create a duplicate table of 7ept with the name !7#6-&7


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WEEK 2:

DML( D$T$ M$AI&L$TI*A L$A$E )

1 IASE3T

The Insert co..#nd is used to #dd one or .ore ro!s to # t#0"eWhi"e usin+ this co..#nd the %#"ues

#re se#r#ted 0 co..#s #nd the d#t#tes ch#r%#rch#r2 #nd d#te #re enc"osed in #ostrohes The

%#"ues .ust 0e entered in the s#.e order #s the #re de/ined in the t#0"e

1 SQL Insert into e. %#"ues ( 1 $3A C$LCTT$ 12$A9


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Co.#tison oer#tors #re used in conditions to co.#re one e4ression !ith #nother The co.#rison

oer#tors #re ? ? ? ? 0et!een ( to chec6 0et!een #n t!o %#"ues)

In ( to .#tch !ith #n o/ the %#"ues in the "ist ) "i6e ( to .#tch # ch#r#cter #ttern )

; SQL Se"ect O /ro. orderin/o !here tot#" ;===


8/45

$SSIAMEAT2

5. Insert all the following data into #M6 table.

'. 7isplays all columns and all rows of the #M6 table.

3. 7isplay specific columns of the #M6 table li2e employee name, salary B department number.

9. alculate a salary increase of 3>> for all employees and displays a new SalC3>> column in the output.

$. insert a new record and gie the data into empno, ename, sal and deptno columns only

. 7isplays the employee name B annual compensation of employees. It calculates the annual

compensation as 5' multiplied by the monthly salary, plus a one time bonus of 5>>.

;. 7isplays employee details as DI0E is a 6#SI7#0- with column heading #mployee 7etails. " usingconcatenation operator, GG B column alias %

(. 7isplays distinct department number from #M6 table.

=. 7isplays employee name, Hob title B department number of all employees whose Hob title is +#D.

5>. 7isplays name, salary B commission from the #M6 table except MA0AE#.55. 7isplays name B salary whose salary is between 5>>> and '>>>.

5'. 7isplays employee number, name, salary B managers employee number of all the employees whose

managers employee number are ;=>', ;$ or ;;((.

53. 7isplays all employee names starting with S.

59. 7isplays all employee names ending with .

5$. Increase the salary of all employees with $J of sal.5. Increase the salary of all managers with 5$J of sal.

5;. update all the comm. Kith '>> whose comm. Are 0>> 5>;=( +AD# MA0AE# ;(3= >5LMA1L(5 '($> 3>

;;(' +AD MA0AE# ;(3= >=LN

;$9 MA-I0 SA+#SMA0 ;=( '(LS#6L(5 5'$> 59>> 3>

$9== A++#0 SA+#SMA0 ;=( '>LF#L(5 5>> 3>> 3>

;(99 -(LS#6L(5 5$>> > 3>

;=>> NAM#S +#D ;=( >3L7#L(5 =$> 3>

;$'5 KA7 SA+#SMA0 ;=( ''LF#L(5 5'$> $>> 3>

;=>' F/7 A0A+1S- ;$ >3L7#L(5 3>>> '>

;3= SMI-O +#D ;=>' 5;L7#L(5 (>> '>

;;(( S/-- A0A+1S- ;$ >=L7#L(' 3>>> '>

;(; A7AMS +#D ;;(( 5'LNA0L(3 55>> '>

;=39 MI++# +#D ;;(' '3LNA0L(' 53>> 5>


9/45

WEEK 8 :SQLO&"us -unctions

Sin+"e3o! -unctions-hese functions operate on single rows only and return one result per row. -here are different types of single

row functions.

5. Ch#r#cter /unctions: accept character input and return both character and number

alues.

'. Au.0er /unctions: Accept numeric input and return numeric alues.

3. D#te /unctions: /perate on alues of the date datatype. All date functions return a

alue of date datatype except the M*ATSBETWEEAfunction, which return anumber.

9. Con%ersion /unctions: onert a alue from one datatype to another.

$. ener#" /unctions:

L 0?+ functionL 7#/7# function

-unctions

Sin+"ero!

/unctions

Mu"ti"ero!

/unctions

Sin+"ero!

/unctions

Ch#r#cter

ener#" Au.0er

D#teCon%ersion


10/45

C#se con%ersion /unctions

-unction 3esu"t

L*WE3( SQL Course )

&&E3 ( SQL Course )

IAITC$& ( SQL Course )

sF" course

SQL C*3SE

SF" Course

Ch#r#cter .#niu"#tion /unctions

-unction 3esu"t

C*AC$T( oodU Strin+ )

SBST3 ( Strin+ 1 8 )

LEAT ( Strin+ )

IAST3 ( Strin+ rU )

L&$D ( s#" 1= OU)

oodStrin+

Str

8

OOOOOO5=== ( e4#."e on" )

3*AD: ounds alue to specified decimal

3*AD" 9$.=',' % 9$.=3

T3AC: -runcates alue to specified decimal

T3AC" 9$.=',' % 9$.='

M*D: eturns remainder of diision

M*D" 5>>, 3>> % 5>>

Ch#r#cter /unctions

C#se con%ersion

/unctions

Ch#r#cter .#niu"#tion

/unctions

L*WE3&&E3

IAITC$&

C*AC$T

SBST3

LEAT

IAST3

L&$D

Au.0er -unctions


11/45

Wor6in+ !ith D#tes

/racle stores dates in an internal numeric format: entury,

year, month, day, hours, minutes, seconds.

-he default date format is 77LM/0L11.

S1S7A-# is a function returning date and time.

7


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3ound

This /unction returns the d#te !hich is rounded to the unit seci/ied 0 the /or.#t .ode"

The /or.#t is round(d/.tX) !here d is the d#te #nd /.t is the /or.#t .ode"

SQL Se"ect round(tod#te(28oct9dd.on)e#r) /ro. du#"

>5LHanL=; will be the result.

SQL Se"ect round(tod#te(28oct9dd.on).onth) /ro. du#"

>5LnoL= will be the result.

Trunc#te

This /unction returns the d#te !ith the ti.e ortion o/ the d# trunc#ted to the unit seci/ied 0 the

-or.#t .ode"The /or.#t is trunc(d/.tX) !here d is the d#te #nd /.t is the /or.#t .ode"

SQL Se"ect trunc(tod#te(28oct9dd.on)e#r) /ro. du#"

>5LHanL= will be the result.

SQL Se"ect trunc(tod#te(28oct9dd.on).onth) /ro. du#"

>5LoctL= will be the result.

C!ARACT#R FUNCT$N%

-ACTI*A IA&T *T&T

Initc#(ch#r) Se"ect initc#(he""o) /ro. du#" e""o

Lo!er(ch#r) Se"ect "o!er(-A) /ro. du#" /un

er(ch#r) Se"ect uer(su.) /ro. du#" SM

Ltri.(ch#rset) Se"ect "tri.(4@#d#.s4@)

/ro. du#"

$d#.s

3tri.(ch#rset) Se"ect rtri.(4@#d#.s#.s)

/ro. du#"

Y@#d

Tr#ns"#te(ch#r/ro.to)

Se"ect tr#ns"#te(#c60) /ro.du#"

B#c6

3e"#ce(ch#rse#rchs

trin+re strin+X)

Se"ect re"#ce(#c6 #nd ue0")

/ro. du#"

B"#c6 #nd

0"ue

Su0str(ch#r.n) Se"ect su0str(#0cde/+82) /ro. du#" Cd

Soundex, which is also a character function compares words that are spelled differently,but sound ali2e.onsider the following example.

SQL Se"ect n#.e /ro. custo.er !here sounde4(n#.e) ? sounde4(s.the)


13/45

/ther two functions are "#dB r#d.

SQL Se"ect "#d(#0c15?) /ro. du#"

-his function returns the sign 4 before the character string abc. -he output gies the

sign 4 before the word function. -he entire string is 5$ in length after the padding is

done.

SQL Se"ect r#d(#0c15?) /ro. du#"

-he rpad function pads the alue gien to the right of the string.

NU"#RC FUNCT$N%

-ACTI*A IA&T *T&T

$0s Se"ect #0s(15) /ro. du#" 15

Cei"(n) Se"ect cei"(;;


14/45

SQL Se"ect tod#te(#nu#r 15 1999 .onthdd ) /ro. du#"

5$LHanL== will be the result.

'R$UP FUNCT$N

3*& -unctions


15/45

sin+ the 3*& BZ C"#use on Mu"ti"e Co"u.ns

SQL se"ect detno o0 SM(s#") /ro. e. 3*& BZ detno o0

1ou can return summary results for groups and subgroups by listing more than one E/


16/45


17/45

1ou cannot use the KO## clause to restrict groups.1ou use the OA?I0E clause to restrict groups.

S*+ S#+#- deptno, A?E"sal%

F/M emp

KO## A?E"sal% '>>>

E/


18/45

Dis"#s the n#.e #nd hire d#tes /or #"" the e."oees The hire d#te "oo6s "i6e 1; Ao%e.0er

19


19/45

WEEK :

*0t#inin+ D#t# /ro. Mu"ti"e T#0"es (oin)

EM& DE&T

7ata from Multiple -ables

Sometimes you need to use data from more than one table. In the example aboe, the report displays data from

two separate tables.

5. EM&A*exits in the EM&table.

'. DE&TA*exits in both the EM&and DE&Ttables.

3. L*Cexits in DE&Ttable.

-o produce the report, you need to lin2 #M6 and 7#6- tables and access data from both of them.

Wh#t is # oin\


20/45

Tes o/ oin

#UuiHoin 0onLeUuiHoin /uter Hoin Self Hoin

-here are two main types of Hoin conditions:

EFuioins

AoneFuioins

Additional Hoin methods include the following:

*uter oins

Se"/ oins

Set oer#tors

EFuioin

A Hoin which is based on eUualities is called an eUuiHoin.

SQL Se"ect e.e.no e.en#.e e.detno detdetno det"oc

-ro. e. det

Where e.detno ? detdetno

In the aboe statement e.detno ? detdetnoperforms the Hoin operation.

It retriees rows from both the tables proided they both hae the same detnocolumn as specified in the

where clause. Since the where clause uses comparison operator eUual to "4%, to perform a Hoin, it is said an

eFuioin.

EFuioins #re #"so c#""ed si."e oins or inner oins

$ddition#" Se#rch Conditions sin+ the $AD *er#tor

For example, to display employee number, name, department number and department location, you need an

additional condition in the KO## clause.

SQL SELECT e.no en#.e e.detno "oc

-3*M e. det WE3E e.detno ? detdetno

$AD IAITC$& ( en#.e ) ? Kin+U


21/45

AonEFuioins$ non eFuioin seci/ies the re"#tionshi 0et!een co"u.ns 0e"on+in+ to di//erent t#0"es 0 .#6in+ use

o/ the re"#tion#" oer#tors ( ?? ) other th#n ?

EM& S$L3$DE

The re"#tionshi 0et!een the EM& t#0"e #nd the S$L3$DE t#0"e is # noneFuiion .e#nin+ th#t no

co"u.n in the EM& t#0"e corresonds direct" to # co"u.n in the S$L3$DE t#0"e The re"#tionshi

0et!een the t!o t#0"es is th#t the S$L co"u.n in the EM& t#0"e is 0et!een the L*S$L #nd IS$Lco"u.n o/ the S$L3$DE t#0"e The re"#tionshi is o0t#ined usin+ #n oer#tor other th#n eFu#" ( ? )

*uter oins

Zou use #n outer oin to #"so see ro!s th#t do not usu#"" .eet the oin condition

*uter oin oer#tor is the "us si+n ( P )

Missin+ ro!(s) c#n 0e returned i/ #n outer oin oer#tor is used in the oin condition It is "#ced on the

side o/ the oin th#t is de/icient in in/or.#tion This oer#tor h#s the e//ect o/ cre#tin+ one or .ore nu""

ro!s to !hich one or .ore ro!s /ro. the nonde/icient t#0"e c#n 0e oined

$ condition in%o"%in+ #n outer oin c#nnot use the IA oer#tor or 0e "in6ed to #nother condition 0 the

*3 oer#tor

Se"/ oinsSo.eti.es ou need to oin # t#0"e to itse"/ To /ind the n#.e o/ e#ch e."oeeUs .#n#+er ou need to

oin the EM& t#0"e to itse"/ -or e4#."e to /ind the n#.e o/ BL$KEUs .#n#+er ou need to :

-ind BL$KE in the EM& t#0"e 0 "oo6in+ #t the EA$ME co"u.n

-ind the .#n#+er nu.0er /or BL$KE 0 "oo6in+ #t the M3 co"u.n BL$KEUs .#n#+er nu.0er is

;


22/45

Set *er#tors

Set operators combine the results of two Uueries into a single one.

nion

nion #""

Intersect

Minus

The queries )hich are relate* +y a set operator shoul* hae the same num+er

o- columns an* the correspon*ing columns must +e o- the same *atatype.

nion

-he union operator returns all distinct rows selected by either Uuery. -he following

example combines the result of two Uueries with the union operator which eliminates

duplicate rows.

SQL Se"ect custid /ro. custo.er union se"ect ordid /ro. orderin/o

nion #""

-he union all operator returns all rows selected by either Uuery including duplicates.

SQL Se"ect custid /ro. custo.er union #"" se"ect ordid /ro. orderin/o

Intersect

Intersect operator returns only rows that are common to both the Uueries.

SQL Se"ect ordid /ro. orderin/o intersect se"ect ite.id /ro. ite.

Minus

Minus operator returns all distinct rows selected only by the first Uuery and

not by the second.

SQL Se"ect ordid /ro. ite. .inus se"ect ordid /ro. orderin/o

Khile using the order by clause, it must follow the last select statement and wemust order by interger and not by column name. onsider the following example.

SQL Se"ect ordidcustid /ro. orderin/o union se"ect ite.idrodid

/ro. ite.order 0 2

-he aboe example displays distinct rows selected by either Uuery, ordered by the

second column stated in both the Uueries. Since the column names are different inthe aboe Uueries, we use an integer in the order by clause instead of a column name.


23/45

$SSIAMEAT

$ Cre#te t#0"e detour ro"" nu.0er !ith /o""o!in+ structure

DE&TA* A*T ALL AMBE3 (2)

DA$ME ,$3C$32 (1)

L*C ,$3C$32 (18)

6ut the alues.

DE&TA* DA$ME L*C

1= $CC*ATIA AEW Z*3K

2= 3ESE$3C D$LL$S

8= S$LES CIC$*

= *&E3$TI*AS B*ST*A

B Cre#te t#0"e S#"+r#deour ro"" nu.0er !ith /o""o!in+ structure

3$DE AMBE3 (2)

L*S$L AMBE3()IS$L AMBE3()

6ut the alues.

3$DE L*S$L IS$L

1 ;== 12==

2 12=1 1==

8 1=1 2===

2==1 8===

5 8==1 9999

E%#"u#te #n e."oeeUs s#"#r +r#de

5 Dis"#s EA$ME DE&TA* DA$ME /or #"" the de#rt.ents The *&E3$TI*AS

de#rt.ent !hich does not h#%e #n e."oees is #"so dis"#ed sorted 0 DE&TA*

Dis"# the /o""o!in+

3E&*3T

BL$KE !or6s /or KIA

CL$3K !or6s /or KIA

*AES !or6s /or KIA

M$3TIA !or6s /or BL$KE

[[[[[

[[[[[


24/45

WEEK 5 :

Say this is a problem.

7 Who h#s # s#"#r +re#ter th#n onesUs \ 7

-o sole this problem, you need two Uueries : one Uuery to find what Nones earns and a second Uuery to find

who earns more than that amount.

1ou can sole this problem by combining the two Uueries, placing one Uuery inside the other Uuery.

Su0Fueries

$ su0Fuer is # SELECT st#te.ent th#t is e.0edded in # c"#use o/ #nother SELECT st#te.ent

In the snt#4:

*er#tor inc"udes # co.#rison oer#tor such #s ? or IA

Co.#rison oer#tors /#"" into t!o c"#sses: sin+"ero! oer#tors ( ? ? ?) #nd .u"ti"ero!

oer#tors ( IA $AZ $LL )

The su0Fuer is o/ten re/erred to #s # nested SELECT su0SELECT or inner SELECT st#te.ent The

su0Fuer +ener#"" e4ecutes /irst #nd its outut is used to co."ete the Fuer condition /or the .#in or

outer Fuer

M#in Quer

7Which e."oees h#%e # s#"#r +re#ter th#n onesUs s#"#r\]

Su0Fuer

7Wh#t is onesUs s#"#r\]

SELECT se"ect"ist

-3*M t#0"e

WE3E e4r oer#tor

( SELECT se"ect"ist

-3*M t#0"e

WE3E e4r )


25/45

E4#."e

SQL SELECT en#.e

-3*M e.

WE3E s#"

( SELECT [[[

-3*M [[[

WE3E [[[[ )

uide"ines /or sin+ Su0Fueries

1 Enc"ose su0Fueries in #rentheses

2 &"#ce su0Fueries in the ri+ht side o/ the co.#rison oer#tor

8 Do not #dd #n *3DE3 BZ c"#use to # su0Fuer

se sin+"ero! oer#tors !ith sin+"ero! suFueries

5 se .u"ti"ero! oer#tors !ith .u"ti"ero! suFueries

Tes o/ Su0Fueries

Sin+"ero! su0Fueries: Queries th#t return on" one ro! /ro. the inner SELECT st#te.ent

Mu"ti"ero! su0Fueries: Queries th#t return .ore th#n one ro! /ro. the inner SELECT

st#te.ent

Mu"ti"eco"u.n su0Fueries: Queries th#t return .ore th#n one co"u.n /ro. the inner

SELECT st#te.ent

3eturn on" one ro!

se sin+"ero! co.#rison oer#tors

/perator Meaning

4 #Uual to

Ereater than

4 Ereater than or eUual to

V +ess than

V4 +ess than or eUual to

V 0ot eUual to

If the inner Uueries return single alues, the S*+ statement is called a singleLrow subUuery. -he outer and the

inner Uueries can get data from different tables.

Zou c#n use rou /unctions in # Su0Fuer

S*+ S#+#- TTTTTT.

F/M TTT.

KO## TT.

" S#+#- MAP"TT.%

F/M TTT % )


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$,IA C"#use !ith Su0Fueries

1 The *r#c"e Ser%er e4ecutes su0Fueries /irst

2 The *r#c"e Ser%er returns resu"ts into the .#in FuerUs $,IA c"#use

S*+ S#+#- TTTTTTTTTTT..

F/M TTTT

E/


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In singleLrow subUueries and multipleLrow subUueries only one column was compared in th e KO## clause

or OA?I0E clause of the S#+#- statement. If you want to compare two or more columns, you must write a

compound KO## clause using logical operators.

Snt#4

D#t#0#se *0ects

Snon.

A synonym is a database obHect, which is used as an alias" alternatie name % for a table,

iew or seUuence.

SQL Cre#te snon. cust /or custo.er

SeFuences

A seUuence is a database obHect which can generate uniUue, seUuential integer alues. It can

be used to automatically generate primary 2ey or uniUue 2ey alues.

-he syntax for the creating a seUuence is as follows.

Cre#te seFuence seFn#.e incre.ent 0 n st#rt !ith n .#4%#"ue n X

.in%#"ue n X cc"e ' nocc"e X c#che ' noc#che X

Incre.ent 0 n : n is an integer which specifies the interal between seUuence

numbers.

St#rt !ith n : Specifies the first seUuence number to be generated.

Min%#"ue n : Specifies the minimum alue of the seUuence.

M#4%#"ue n : It specifies the maximum alue that the seUuence can generate.

Cc"e : Specifies that the seUuence continues to generate alues after reaching

either its max or min alue.

Aocc"e : Specifies that the seUuence cannotgenerate more alues after reaching

either its max or min alue.

C#che : Allows faster generation of seUuence number. /racle preallocates seUuence numbers and 2eeps them in memory for faster access.

-he cache alue must be less than maxalue minus minalue.

SELECT co"u.n co"u.n [

-3*M t#0"e

WE3E ( co"u.n co"u.n [) IA

( SELECT co"u.n co"u.n [

-3*M t#0"e

WE3E condition )


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Aoc#che : 7oes not preallocate seUuence numbers for faster access.

SQL Cre#te seFuence custseF incre.ent 0 1 st#rt !ith 1 .#4%#"ue 1=

Min%#"ue 1 cc"e c#che

After creating a seUuence we can access its alues with the help of pseudocolumns li2e

curr%#"and ne4t%#". A pseudocolumn behaes li2e a table column, but it not actually stored

in the table.

Ae4t%#" :0extal will return inital alue of the seUuence, when referred to, forthe first time. +ater reference to nextal will increment the seUuence alue

by I0#M#0- 1 clause and return the new alue.

Curr%#" : urral returns the cuttent alue of the seUuence which is the alue returned

y the last reference to nextal.

SQL Cre#te t#0"e te. ( id nu.0er(8) n#.e %#rch#r2(2=))

SQL Insert into te. %#"ues ( custseFne4t%#" %i#)

-o find out the current seUuence number

SQL Se"ect custseFcurr%#" /ro. te.

$"ter seFuence

Ke can alter the seUuence when we want to do the following :

Set or eliminate min or max alue. hange the increment alue.

hange the number of the cached seUuence numbers.

-he following example will change the maxalue of the seUuence from 5> to 5$.

SQL #"ter seFuence custseF .#4%#"ue 15


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$SSIAMEAT 5

5. Kho has a salary greater than NonessX

'. Kho has a salary greater than the salary of employee ;$.

3. 7isplay the employees whose Hob title is the same as that of employee ;3=.9. 7isplay the employees whose Hob title is the same as that of employee ;3= and whose salary is

greater than of employee ;(;.

$. 7isplays the employee name, Hob title and salary of all employees whose salary is eUual to the

minimum salary.

. 7isplays all the departments that hae a minimum salary greater than that of department '>.;. Find the Hob with the lowest aerage salary.

(. Find the employees who earn the same salary as the minimum salary for department.

=. 7isplays the employees whose salary is less than any cler2 and who are not cler2s." hint: -he maxsalary that a cler2 earns is 53>> so the S*+ statement displays all the employees who are not cler2s

but earn less than 53>>%

5>. 7isplays employees whose salary is greater than the aerage salaries of all the departments. " hint: the

highest aerage salary of a department is '=5., so the Uuery returns those employees whose salary

is greater than '=5.%

55. 7isplay the name, department number, salary and commission of any employee whose salary and

commission matches both the commission and salary of any employee in department 3>.


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WEEK 6

PL/SQL Tutorial

PL/SQL BLOCK : The pl/sql block contains the following section:--

The DECLAREsection.

The Master BEGINand ENDsection that contains the

EXCEPTIONsection.

The declare section contains declaration of memory variables, constants,cursors etc. The begin section contains sql eecutable statements and

pl/sql eecutable statements. The eception section contains code tohandle errors that may arise during the eecution of the code block. The

end declares the end of pl/sql block.

! bit about it"s working. #hen you typed out the pl/sql block foreecution. $t is sent to the pl/sql engine, where procedural statements

are eecuted% and sql statements are sent to the sql eecutor in the

oracle engine. &ince pl/sql engine resides in the oracle engine, the codeseecutes smoothly and efficiently.

PL/SQL DATA-TYPE :

This is easy since it includes almost all the data types which u have usedin sql such as date, varchar, number, char etc etc.. &ome of the

attributes such as 'T()* is also used. This attribute automatically takesin the default data type of the sql table from which u have passed the

query. #e will discuss this later.

+emember in pl/sql a variable name must begin with a character and can

be followed by maimum of other characters. +eserved words can"tbe used unless enclosed within double quotes. ariables must be

separated from each other by at least one space or by a punctuationmark. (ou can assign values of operator using : operator. $ won"t

discuss about logical comparisons operators such as 0, 1 , 1, 23T,T+4*, !25, 3+, 2466 etc since they r quite easy to understand.

OW TO DISPLAY !ESSAGES ON SCREEN :

DB!S"O#TP#T :is a $a%&a'(that includes a number of procedure and functions

that accumulate information in a buffer so that it can be retrieved later. These functionscan also be used to display messages to the user.

P#T"LINE :)ut a piece of information in the package buffer followed by an end-of-linemarker. $t can also be used to display message to the user. )ut7line epects a single

parameter of character data type. $f used to display a message, it is the message


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"string".

*8: dbms7output.put7line9%

RE!E!BER: To display messages to the user the &*+*+34T)4T should be set to 32.&*+*+34T)4T is a sql ;plus environment parameter that displays the information on

screen passed as a parameter to the )4T76$2* function.

EG: SET SER)ERO#TP#T ON

PL/SQL %o**(+t, :

! comment can have forms i.e.-- The comment line begins with a double hyphen 9--. The entire line will be treated as

a comment.-- The < style comment such as /; i am a comment ;/

EXA!PLE :

--ADDITION O TWO N#!BER5eclare

a number%

b number%c number%

=egin

a:>a%b:>b%

c:a?b%dbms7output.put7line9"&um of " @@ a @@ " and " @@ b @@ " is " @@ c%

*nd%

Aere B>C symbol is used to take user input at runtime.....

CONDITIONAL CONTROL :

S.+ta :$D --b%

dbms7output.put7line9"*nter c:"%

c:>b%


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if 9a1b and 9a1c thendbms7output.putline9"! is Maimum"%

elsif 9b1a and 9b1c thendbms7output.putline9"= is Maimum"%

elsedbms7output.putline9"< is Maimum"%

end if%*nd%

Ea*$l( 4: 1CALC#LATION O NET SALARY3

declare

ename varchar9EF%basic number%

da number%hra number%

pf number%netsalary number%

beginename:>ename%

basic:>basic%

da:basic ; 9GE/EHH%hra:basic ; 9EF/EHH%

if 9basic 0 IHHH

thenpf:basic ; 9F/EHH%

elsif 9basic 1 IHHH and basic 0 FHHHthen

pf:basic ; 9J/EHH%elsif 9basic 1 FHHH and basic 0 KHHH

thenpf:basic ; 9K/EHH%

else

pf:basic ; 9EH/EHH%end if%netsalary:basic ? da ? hra -pf%

dbms7output.put7line9"*mployee name : " @@ ename%dbms7output.put7line9")rovidend Dund : " @@ pf%

dbms7output.put7line9"2et salary : " @@ netsalary%end%

ITERATI)E CONTROL AND SEQ#ENTIAL CONTROL

5. SI!PLE LOOP

S.+ta :loop

-- &equence of statements%-- the loop ends when u use *L$T #A*2 statement --condition

end loop%(a*$l( :

5eclare n number:E%6oop

5bms7output.put7line 9n%n:n?E%

*L$T #A*2 n1F%

*nd loop%


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45 WILE LOOP

S.+ta :#hile --condition

loop--sequence of statements

end loop%

Ea*$l( :

--S#! O ODD N#!BER WITIN 7

declare

n number%sumE number default H%

beginn:E%

while 9n 0 FHloop

sumE:sumE?n%n:n?%

end loop%dbms7output.put7line9"&um of odd numbers :" @@ sumE%end%

$SSIAMEAT

5. Krite a program using 6+YS*+ to input an integer and chec2 whether a year is +eap year or not.

'. Krite a program to chec2 the salary of W+AD# from #M6 table. If it is V5>>> then increment comm

with >> else show message ! 0/ I0#M#0- 8 .

3. Krite a program to display 5st'> odd numbers " suing simple loop%

9. Krite a program using to input an integer and display it in reerse order"using Khile loop%

$. Krite a program using to input an integer and chec2 whether it is prime or not.

WEEK 825 OR LOOPS.+ta :

Dor i in E..EH

loop--sequence of statementsend loop%

Ea*$l( 0 :

5eclarebegin

for i in E..EHloop

dbms7output.put7line9i%end loop%

end%


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Ea*$l( 4 : 1S#! O ODD N#!BERS WITIN 73

declaren number%

sumE number default H%

begin

n:E%for n in E.. FH

loop

if mod9n,E thensumE:sumE?n%

end ifend loop%

dbms7output.put7line9"sum " @@ sumE%end%

95 GOTO : 1SEQ#ENTIAL CONTROL3

S.+ta :

83T3 L%00 L 11

declare

--takes the default datatype of the column of the table pricemsal emp.sal'type%

beginselect sal into msal from emp where empnoJHH%

if msal 1 JHHH thengoto 4pd%

elseupdate emp set salsal?FHH where empnoJHH%

end if%

00 4pd 11dbms7output.put7line 9 $2


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$r((;i+( (%($tio+,: are already defined within datadictionary. Dollowing are some eamples of )redefined eceptions

EXCEPTION

2o-data-found when no rows are returned


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=*8$2

&*6*

*25%

WEEK =

C3S*3:


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EXA!PLES

--EXA!PLE O SQLO#ND 1I!PLICIT C#RSORS3

begin

update emp set salsal ;H.EF where empno >emp7code%if sql'found then

dbms7output.put7line9"employee record modified successfully"%

elsedbms7output.put7line9"employee does not eist"%

end if%end%

--EXA!PLE OR SQLNOTO#ND 1I!PLICIT C#RSORS3

beginupdate emp set sal sal;H.EF where empno >emp7code%

if sql'notfound then

dbms7output.put7line9"employee does not eist"%else

dbms7output.put7line9"employee record modified successfully"%end if%

end%

--EXA!PLE OR SQLROWCO#NT 1I!PLICIT C#RSORS3

declare

rows7affected char9G%begin

update employee set salary salary;H.EF where Oob"programmers"%rows7affected : to7char9sql'rowcount%if sql'rowcount 1 H then

dbms7output.put7line9rows7affected @@ "employee records modifiedsuccessfully"%

else

dbms7output.put7line9"There are no employees working asprogrammers"%

end if%end%

S.+ta of eplicit cursor:


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3)*2 cE%

633)D*T


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TRIGGER:

Trigger is a stored procedure which is called implicitly by oracle

engine whenever a insert, update or delete statement is fired.

Aa+ta'(, o; ata>a,( tri''(r,:

---1 5ata is generated on it"s own

---1 +eplicate table can be maintained

---1 To enforce comple integrity constraints

---1 To edit data modifications

---1 To auto increment a field

etc..

S.+ta:


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41/45

WEEK

PROCED#RES AND #NCTIONS

procedure is a subprogram...which consists of a set of sql statement.

)rocedures are not very different from functions. ! procedure or functionis a logically grouped set of &6 and )6/&6 statements that perform a

specific task. ! stored procedure or function is a named pl/sql code blockthat have been compiled and stored in one of the oracle engineCs systemtables.

To make a procedure or function dynamic either of them can be passed

parameters before eecution. ! procedure or function can then change

the way it works depending upon the parameters passed prior to itseecution.

Pro%(ur(, a+ ;u+%tio+ ar( *a( u$ o;

5eclaration part

*ecutable part

*ception-handling part93ptional

! declaration part consists of declarations of variables. !eecutable part consists of the logic i.e. sql statements....and

eception handling part handles any error during run-time

T@( ora%l( (+'i+( $(r;or*, t@( ;olloi+' ,t($, to ((%ut( a

$ro%(ur( or ;u+%tio+5555

erifies user access

erifies procedure or function validity

eecutes the procedure or function

So*( o; t@( aa+ta'(, o; u,i+' $ro%(ur(, a+ ;u+%tio+, ar(:

&ecurity

)erformance

memory allocation

productivity integrity.

!o,t i*$orta+t: 1the i;;(r(+%(between $ro%(ur(,and;u+%tio+,

! function must return a value back to the caller. ! function canreturn only one value to the calling pl/sql block. =y defining multiple

out parameters in a procedure, multiple values can be passed to the

caller. The out variable being global by nature, its value is accessibleby any pl/sql code block including the calling pl/sql block.


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S.+ta ;or ,tor( $ro%(ur(:


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EXA!PLE 0:

--)+3


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WEEK 07

PACKAGE:

! package is an oracle obOect, which holds other obOects within it.

3bOects commonly held within a package are procedures, functions,

variables, constants, cursors and eceptions. )ackages in plsql arevery much similar to those packages which we use in S!!.

Part, o; $a%&a'( :

Pa%&a'( ,$(%i;i%atio+

Pa%&a'( >o.

! $a%&a'( ,$(%i;i%atio+part consists of all sort of declarationof functions and procedures

#hile package body consists of group of code and logic of declaredfunctions and procedures.

EXA!PLE

--package specification 9save into file packEcreate or replace package pack is

Dunction rmt9 in number return number%procedure rmtE9 in number%

end%

--body 9save into file p

create or replace package body pack is

Dunction rmt9 in number return number is

begin

return 9;%end%

procedure rmtE9 in number is

begindbms7output.put7line9;%end%

end%

-- To eecute the package at first run the pE file and then p file

and then from &6 prompt type eec pack.rmtE9I%

!s shown above u can put in complicated procedures and functionsinside the package. $ have Oust shown a simple eample. (ou can

easily modify the above code to fit your requirement. Sust try out


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packages which include cursors, procedures and functions etc.

+emember pl/sql supports overloading. i.e. you can use the samefunction or procedure name in your application but with different

no or type of arguments.

DBMS Introduction to SQL

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