INFORMATION
TECHNOLOGY
for
P.C.C.
 PROF. ZULESH DEDHIA
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
FLOWCHARTS
I n o r de r to co m mu n i c a te w i t h the c o m pu te r , a co m p u te r l a n gu a ge i s u se d .
H o we ve r , s i n ce t h e c o m pu te r d o e s n o t h a ve i ts o w n b r a i n s , i t i s f o o l i sh to
e x pe c t co m m o n se n se f r o m i t . The r e fo re , t o ge t t he c o m pu te r t o pe r fo r m o n e
t a s k , a s e r i e s o f i n s t r u c ti o n s a re t o be gi ve n i n a c o m pu te r l a n gu a ge .
A p ro g r a m i s a se t to i n s t r u ct i o ns g i ve n to t he co m p u te r by t he u se r , i n a
c o m pu te r l a ng u ag e , t o g e t t h e c o m p u te r t o pe r f o rm a c e r t a i n t a s k. Th e se
i n s t ru c ti o n s a re to be de fi n e d i n a p r o pe r se qu e nce an d no t h a ph a z a r d l y g i ve n .
Th i s s pe c i fi c se qu e n ce o f i n s t ru c ti o n s de si gne d t o ge t the de si re d re s u l t i s
c a l l e d a n A l go r i t h m .
D i ag r a m m a t i c a l pr e se n t a ti o n o f a n A l g o r i t h m i s k no wn a s F l o w c h a r t . Th u s , a
F l o w ch a r t i s a pi c t o r i al p re se n t a t i o n o f the se qu e nce o f s te p s i nv o l ve d i n
s o l v i n g a p r o bl e m .
S Y M BO LS U S ED IN F LO W C H A R T :
1. START/END
2. INSTRUCTION FLOW LINE
OR
3. INPUT/OUTPUT
4. PROCESS
5. DECISION
6. ON-PAGE CONNECTOR
7. OFF-PAGE CONNECTOR
8. PRINT
9. DISPLAY
10. ONLINE STORAGE/FLOPPY DISC
11. MAGNETIC TAPE / SEQUENTIAL ACCESS
STORAGE
2
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
I l l u s t r a t i o n : C o mpu t e a n d pr i n t s i m pl e i n t e r e s t .
START
INPUT P,R,N
I = P*R*N/100
PRINT I
END
P , R , N & I a r e v a r i a b l e s a s t h e y c a n a s s u me a ny v a l u e , i . e . , t he i r v a l u e i s n o t
fixed.
LOOP
W he n s o me po r t i o n o f a p ro g r a m i s t o be e x e c u te d r e pe t i ti v e l y , we c r e a te a
l o o p . Th i s l o o p m ay be se t a cc o r di ng t o t he h a p pe n i n g o f ce r t ai n co n di t i o n o r i t
m a y b e p re se t f o r s pe ci f i e d n u m be r o f t i me s .
L o o p se t a c co r d i n g t o t h e h a p pe n i ng o f ce r t a i n co nd i ti o n – A n i l l u st r a t i o n :
START
INPUT P,R,N
I = P*R*N/100
PRINT I
MORE
RECORDS?
YES
NO
END
3
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
L o o p s e t f o r s pe c i f i c n u m b e r o f t im e s - A n i l l u s t r a t i o n :
F i n d a n d pr i n t f i rs t 1 0 mu l t i pl e s o f a n u m b e r :
START
INPUT N
C=1
M = N*C
PRINT M
IS
C = 10?
NO
C = C+1
YES
END
C O U N T ER : A co u n te r i s a v a r i a bl e u se d to
t he c o u nte r re a ch e s th e p re - se t v al u e , the
u se o f t he co u n te r m a y b e o f t wo t ype s - o ne
n u m be r o f t i me s a n d o th e r a s a v a r i a b l e f o r
e x a m p l e , a c o u n te r “ C ” h a s be e n u se d a n d i t
s to re t he c o u n t o f t he l o o p. W h e n
p ro g r a m ge t s o u t o f t he l o o p . Th e
f o r pe r f o rm i n g the l o o p a s p e c i fi e d
co m p u t a t i o n pu r p o se . I n the a b o ve
se r ve s b o th t he pu r p o se s .
A C C U M U L A T O R : A me mo r y w h i ch i s u se d to s to re i nte r m e di a te re su l ts d u r i n g
t he e x e c u t i o n o f l o o p i s c a l l e d a cc u m u l a to r . I t i s ge ne r a l l y u se d f o r co m p u ti n g
c u m u l a t i ve re su l ts o f m a t h e m a t i c al e x p re s si o n wi t hi n t he l o o p . A c cu m u l a to r s
a r e u su a l l y g i ve n a n i n i t i al v a l u e 0 o r 1 de pe n di ng u p o n t he l o g i c o f th e
p r o g r a m . I f t h e a c c u mu l a to r i s u se d to a c cu m u l a te a s u m , i n i t i al va l u e o f
a c c u mu l a to r i s g i ve n 0 . I f th e p r o du c t o f a se r i e s i s t o be co m pu te d , t he i n i ti al
v a l u e o f a c c u mu l at o r i s g i ve n a s 1 .
4
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
D r a w a f l o w ch a r t t o f i n d t h e su m of f i r s t 1 0 0 od d n um b e r s .
START
S=0
A=1
S=S+A
A=A+2
15
A > 199
?
YES
PRINT S
STOP
H e re , S h a s be e n u se d a s a n a c cu mu l a to r a n d i t s i ni t i a l v a l u e i s t a ke n a s 0 .
A R R A Y S : A v a r i a bl e c an s to re a n d re p re se n t o nl y o ne v a l u e . So me ti me s i t i s
r e q u i re d to s to re a l i s t o f v a l u e s a n d r e fe r t he n b y a c o m m o n n am e . E . g .
p r o d u c t i o n o f 1 2 m o n th s o f a y e a r i s a s e t o f s i m i l a r i te m s a n d we w o u l d l i ke to
u se the s a me n a me to re fe r t o t h i s l i s t o f v a l u e s . W e m a y u se P 1 , P 2 , . . . . . . P 1 2
a s v a r i a b l e n a me s . Th i s e n su re s th a t di f f e re n t v a r i a b l e s be l o n gi ng to s a me
c l a s s a re c al l e d b y a s i n g l e n a me . E x a m p l e P . Th e 1 , 2 ,3 , . . . . . . u s e d i n the a b o ve
v a r i a b l e s a re c a l l e d s u b sc r i p t s a nd P 1 , P 2 e t c . a re s u bsc r i p te d v a r i a bl e s .
5
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
I l l u s t r a t i o n : D r aw a f l o w c h a r t t o a c c e pt m a r k s o f s t u d e n t s i n s ix s u b j ec t s
a n d pr i n t a v e r a g e m a r k s .
STARTS
READ M (X); X = 1,2, ---6
S=0
X=1
S = S + M(X)
X = X+1
NO
IS
X > 6?
YES
A = S/6
PRINT A
NO
MORE
RECORDS ?
YES
STOP
6
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
S o l v e d P r o b l e m s O n F l o w ch a r t s :
Q 1 . D r a w a f l ow ch a r t t o pr i n t
numbers.
the
higher
of
any
given
two
START
READ A, B
IS
A > B?
YES
PRINT A
NO
PRINT B
STOP
Q2.
D r a w a f l o w ch a r t t o f i n d t h e su m of f i r s t 1 0 0 od d n um b e r s .
START
S=0
A=1
S=S+A
A=A+2
NO
IS
A > 199
?
YES
PRINT S
STOP
7
unique
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q3.
D r a w t h e pr o g r a m f l o w ch a r t f o r f i n d in g t h e s um of s q u a r e s o f f i r s t 2 0
odd numbers
START
S=O
A=1
S=S+A*A
A=A+2
NO
IS
A > 39
?
YES
PRINT
STOP
8
S
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q4.
D r a w a f l ow c h a r t t o pr i n t t h e f a c t o r i a l o f a n y g i v e n po s i t i v e n on - z er o
integer K. (The Fctorial of K is defined as: 1 * 2 * 3 * ... * K).
START
READ K
P=1
A=1
P= P*A
A=A+1
NO
IS
A>K
?
YES
PRINT
STOP
9
P
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q5.
D r a w t h e f l ow c h a r t w h i c h w i l l c a l c u l a t e t h e s u m o f
m u l t i pl e s o f a n i n t e g e r K , i . e . , 1 * K + 2 * K + . . . + N * K
START
READ N, K
S=O
C=1
S=S+C*K
C=C+1
NO
IS
C>N
?
YES
PRINT
S
STOP
S – S u m o f t he g i ve n se r i e s
N – N u m be r o f m u l t i p l e s
K – I n t e ge r
10
the
first
N
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q6.
D r a w a f l o w ch a r t t o pr i n t t h e s u m o f t h e f o l l o w in g se r i e s :
1
2
3


 ...N
2.3 3.4 4.5
terms.
START
READ N
S=0
C=1
S = S + C/[(C + 1) * (C + 2)]
C=C+1
NO
IS
C>N
?
YES
PRINT
STOP
11
S
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q7.
D r a w a f l o w ch a r t t o g e n e r a t e t h e F i b on a c c i n u m be r s : 1 , 1 , 2 ,3 , 5 , 8 ,1 3 ,
. . . , N t e r m s ( i n th e F i b o n a c c i s e r i e s , e a c h n um b e r i s e q u a l t o t h e s u m
o f t h e pr e v i o u s t w o n u m b e r s ) .
START
READ N
FN = 1
SN = 1
PRINT
FN, SN
C=3
TN = FN + SN
PRINT TN
FN = SN
SN = TN
C=C+1
NO
IS
C>N
?
YES
STOP
12
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q8.
D r a w a pr o g r a m f l o w c h a r t t o f i n d t h e b i g g e s t o f t h re e n um b e r s Q 1 , Q 2
a n d Q 3 . T h e b i g g e s t i s s t o r e d i n l oc a t i o n H .
START
READ Q1,Q2,Q3
H = Q1
IS
H < Q2
?
YES
H = Q2
NO
IS
H < Q3
?
NO
PRINT H
STOP
13
YES
H = Q3
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q9.
T h e w e i g h ts o f n e w l y b o rn b a b ie s i n a h o s pi t a l a r e i n pu t t o a
c o m pu t e r . T h e h o s pi t a l i n c h a r g e i s i n t e r e s t e d t o fi n d t h e m ax im u m ,
m i n i mu m an d m e a n w e i g h t s of a l l t h e b a b i e s. D r a w a s u i t a bl e
flowchart
START
READ N
READ W
H=W
L=W
TW = W
C=2
IS
C≤N
NO
YES
MW = TW/N
READ W
PRINT MW,H,L
TW = TW + W
IS
W > H?
NO
STOP
YES
H=W
NO
IS
W<L
?
YES
L=W
C=C+1
H = H I G H ES T W E I G H T / L = L O W E S T W E I G H T / T W = T O TA L W E I G H T
N = N U M B E R O F BA B I E S / W = W E I G H T O F A B O B Y
14
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 10 . A c o m pa n y g i v e s d i s c o u n t t o i t s c us t o m e r s o n th e f ol l o w i n g b a s i s :
Th e a dj o i n i n g di sc o u n ts a re a l l o we d , i f t he c u s to me r ’ s b a l a n ce i s be l o w
R s . 5 0 , 0 0 0 , o t h e rwi se th e r a te o f d i sco u n t i s re du ce d b y 2 % .
Q u an t i ty O r de re d
N o r m a l D i s co u n t
1 – 399
6%
400 – 599
8%
600 – 799
10%
800 – 999
12%
1 , 0 0 0 a n d a b o ve
15%
START
READ Q, BAL
IS
YES
Q < 400
?
D=6
NO
IS
YES
Q < 600
?
NO
D=8
IS
YES
Q < 800
?
NO
IS
Q < 1000
?
NO
D = 10
YES
D = 12
D = 15
IS
BAL < 50000
?
YES
PRINT D
STOP
15
NO
D = D-2
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 11 . D r a w t h e f l o w ch ar t f o r f i n d i n g t h e a m o u n t o f a n a n n u i t y o f Rs . A i n N
y e a r s , r a t e o f i n t e r e s t = r % , R = 1 + r a n d t h i s am ou n t i s g i v en b y th e
following series:
S = A + AR + AR2 + ... + ARN-1
START
READ A, r, N
R=1+r
S=O
C=O
S = S + A * R ^C
C=C+1
NO
IS
C>N–1
?
YES
PRINT
STOP
16
S
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 12 . A s s u m e th a t i m po r t e d g o o d s f r om f o r e i g n c o un t r i e s a r e c l a s s i f i e d i n to
4 c a t e g o r i e s f o r t h e pu r po s e o f l e v y i n g c u s t o ms d u t y . T h e r a t e f o r
each category is as follows:
Class/Categories (K) Categories of Goods
C u s t o m Du t y ( % )
O n V a l u e s of G o od s ( V )
1
F o o ds , b e v e r a g e s
8
2
C l o t h i n g , f o o tw e a r
12
3
Heavy machinery
15
4
L ux u r y i t e m s
20
D r a w t h e f l ow c h ar t f o r c o m pu t i n g t h e a pp r o pr i a t e c u s t o m s d u t y .
START
READ K, V
IS
K=1 ?
YES
CD = 0.08*V
NO
IS
K=2?
YES
CD = 0.12*V
NO
IS
K=3?
NO
CD = 0.20*V
PRINT CD
STOP
17
YES
CD = 0.15 * V
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 13 . D r a w
a
f l o w ch a r t
to
calculate
the
c o m m is si o n
of
a
s a l es
r e pr e s e n t a t i v e b a s e d o n t h e f o l l ow i n g s e t o f r u l e s :
(i)
I f t h e s a l e s i s l e ss t h a n Rs . 5 , 00 0 , t h e r e i s n o c o m mi s s i o n .
(ii)
I f t h e s a l e s is Rs . 5 , 0 00 o r a b o v e b u t l e ss t h an Rs . 5 0 , 00 0 , t h en
t h e c o m m i s s io n is
c o m pu t e d @ 1 0 % o f t h e s a l e s .
( i i i ) I f t h e s a l e s i s Rs . 5 0 , 00 0 o r a b o ve , t h e c o m m is s i on i s Rs . 5 , 0 0 0
a n d @ 1 2 % o f th e s a l e s a b o v e R s . 5 0, 0 0 0 .
P r i n t t h e s a l e s a n d t h e c o m m i ss i o n .
START
READ S
IS
S<5000
?
NO
NO
S<50000
?
NO
YES
YES
C=5000+0.12*(S-50000)
PRINT S, C
STOP
18
C=O
C=0.10*S
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 14 . T h e pr o b l e m i s t o c o m pu t e , f o r a s e r i e s o f t r a n s a c t i o n s , t h e g r o s s
s a l e s ( G ) : t h e q u a n t i t y d i s c ou n t s , ( D ) , i f a n y ; an d t h e n e t s a l e s ( N ) .
T h e r a w d a t a t o b e s u ppl i e d i n t h e pr o g r a m i n c l u d e s t h e q u a n t i t y s o ld
( Q ) a n d u n i t pr i c e ( P ) . T h e q u a n t i t y d i s c o un t s c h e du le i s a s f o l l o w s :
I f q u a n t i t y so l d is :
T h e d i s c o un t r a t e w o u l d b e
L e s s t h an 1 , 0 0 0 u n i t s
5%
1 , 0 00 t o l e s s t h an 2 , 0 0 0
12.5%
2 , 0 00 a n d o v e r
20%
START
READ Q, P
GS = Q*P
IS
Q<1000
?
NO
IS
Q<2000
NO
D=0.20*GS
NS = GS – D
PRINT GS, D, NS
NO
IS
THIS
LAST RECORD
?
YES
STOP
19
YES
YES
D = 0.05*GS
D=0.125*GS
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 15 . D r a w a f l o w c h a r t t o c o m pu t e a n d pr i n t t h e I n c o m e - t ax an d Su r c h a rg e
o n th e i n c om e o f t h e i n d i v i du a l . T h e i n c o m e i s t o b e r e a d f r o m th e
t e r m i n a l a n d t h e t ax is t o b e c a lc u l a t e d a c c o r d i n g t o t h e f o l l ow in g
rates:
Income (in Rs.)
Rate
U pt o 5 0 , 0 0 0
N o t ax
F r o m 50 , 0 0 1 t o 6 0 , 0 0 0
10%
of
th e
amount
ex ce e d s
R s . 50 , 0 00
F r o m 60 , 0 0 1 t o 1 , 5 0 , 0 0 0
R s . 1 , 00 0 + 20 % of t h e a m ou n t a b ov e
R s . 6 0 , 0 00
Above 1,50,000
R s . 19 , 0 00 + 30% o f t h e a m o u n t
a b o v e R s . 1 , 50 , 0 00
T h e s u r c h a r g e i s l e v i e d @ 5 % o n t h e a m o u n t o f t o t a l t ax , i f t h e i n c ome
ex c e e d s Rs . 6 0 ,0 0 0
START
READ I
IS
I ≤ 50000
?
YES
T=0
S=0
NO
IS
I ≤ 60000
?
YES
T=0.10*(O-50000)
S=0
NO
IS
YES
I ≤ 150000
?
T=1000+0.20*(I-60000)
S=0.05*T
NO
T=19000+0.30*(I-150000)
S=0.05*T
PRINT I, T, S
STOP
20
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q16.
Draw a flowchart to illustrate the following situation:
Vishnu Limited calculates discounts allowed to customers on the following basis:
Order Quantity
Normal Discount
1 – 99
5%
100 – 199
7%
200 – 499
9%
500 and above
10%
These discounts apply only if the customers account balance is below Rs.500 and does
include any item older than three months. If the account is outside both the limits,
above discounts are reduced by 2%. If only one condition is violated, the discounts
reduced by 1%. If a customer has been trading with Vishnu Limited for over 5 years
conforms to both of the above credit checks, than he is allowed an additional 1%.
START
Q= Quantity
C = customer balance
I = Item period (months)
D = discount
T = Trading period
INPUT Q, C, I, T
IS
YES
Q < 100
?
D=5
NO
IS
Q < 200
?
YES
D=7
NO
IS
YES
Q < 500
?
D=9
NO
D = 10
IS
YES
C < 500
IS
I<3
NO
IS
I<3
NO
YES
YES
IS
T>5
NO
YES
D= D+1
D = D -1
NO
D=D–2
PRINT D
STOP
21
not
the
are
and
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 1 7 . M a r k s o f e a c h s tu d e n t ( in a c l a ss) i n 1 2 pa pe r s a r e e n t e r e d t h r ou g h
k e y b o a r d o f a t er m i n a l a n d a r e re a d i n t o t h e CPU l o c a t i o n s M A RK S
0 0 1 t o M A RK S 0 1 2 . D r a w th e f l ow c h a r t f o r c o m pu t i n g a n d pr i n t in g
t h e a v e r a g e m a r k s o f e a c h s t u d en t.
START
READ R, M(X);X = 1,2,3,....12
S=O
X=1
S = S + M(X)
X=X+1
NO
IS
X > 12 ?
YES
A = S/12
PRINT R, A
NO
IS
THIS LAST
RECORD ?
YES
STOP
R = ROLL No.
M ( X) = M a r k s i n S u b j e c t X
S = To t a l M a r k s
A = A ve r a ge M a r k s
22
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q18.
A company has 5,000 employees. Their salaries are divided in following
categories:
(i)
Less than Rs.5,000
(ii)
Rs.5,000 to Rs.10,000
(iii)
Rs.10,001 to Rs.15,000
(iv)
Above Rs.15,000
Draw the flowchart to find
the percentage of the employees in
each category.
START
READ S(X); X = 1,2,3, ....., 5000
X=1
A=O
B=0
C=O
D=O
IS
S(X)<5000 ?
YES
NO
IS
YES
S(X) ≤ 10000?
A=A+1
B=B+1
NO
IS
YES
S(X) ≤ 15000 ?
NO
D=D+1
X=X+1
NO
IS
X > 5000 ?
YES
P1 = A/50
P2 = B/50
P3 = C/50
P4 = D/50
PRINT P1, P2, P3, P4
STOP
23
C=C+1
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
Q 1 9 . P r i c e s f o r t e n c o m m o d i t i e s in t h e c u r r e n t y e a r a r e d e s i g n a t e d b y J ( X) ,
X v a r y i n g f r o m 1 t o 2 5 . L ik ew i s e , th e i r l a s t y e a r ’ s pr i c e s a r e
d e s i g n a t e d b y K (Y ) , Y v a r y i n g f r o m 1 t o 2 5 . D r a w t h e f l ow c h a r t f or
f i n d in g h e n u m b er , N o f c o m m o d i t ie s o f w h i ch pr i c e s h a v e i n c r e a s e d .
START
READ J(X); X = 1,2,3, ....., 25
READ K(Y); Y = 1,2,3, ....., 25
X=1
Y=1
N=0
NO
IS
J(X)>K(Y)
?
X=X+1
Y=Y+1
NO
IS
X > 25
?
YES
PRINT N
STOP
24
YES
N=N+1
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
DECISION TABLES
A de c i s i o n t a bl e i s a t a b u l a r p r e se nta t i o n o f p r o g r a m l o gi c . I t d i s p l ay s a l l
c o nd i ti o n s a f fe c ti n g a p a r t i cu l a r si t u a t i o n . I t gi ve s ap p r o p r i a te a ct i o n o r
a c t i o n s to be t a ke n f o r e a ch se t o f c o n di t i o n s .
D e ci si o n t a bl e s a r e u se f u l w he n a co m p u te r h a s t o ma k e l a r ge nu m be r o f
d e c i s i o ns o r i f t h e re a re a l a r ge nu m be r o f di f f e re nt b r a n c he s wi th i n a
program.
C o m po n e n t s of a d e c i s i o n t a b l e :
Table Heading
C o n d i t i on
Stub
Action
Stub
D e c i s i o n R u l e s He a d i n g
C o n d i t i on
Entries
Action
Entries
T a b l e H e a d i n g : T h e n a me o r n u mb e r o f the D e c i si o n Ta b l e s pe c i f yi n g th e
p r o b l e m w hi ch i s b e i n g re p re se n te d . F o r c o m pl e x p r o bl e m s , t he de ci si o n t a bl e
i s so me ti me s b r o ke n i n to p a r t s w he re t he Ta b l e he ad i ng wo u l d i de n t i fy th e p a r t
o f t he p r o g r a m b e i n g re p re se n te d .
C o n d i t i on S tu b : Th e co n di ti o n s t ha t c o u l d e x i s t i n t he p r o g r a m l o g i c are
d e s c r i be d .
A c t i o n S tu b : Th e a c t i o n s t a te me n ts o r po s si bl e o u tc o me s o f the s y ste m a re
d e s c r i be d .
D e c i s i o n Ru l e s : Th e se m a y be o ne o r m o r e de ci si o n r u l e s n u m be re d 1 , 2 ,3 . . . . n
r e p re se n ti ng th e a n s we r s t o t h e Co n di t i o n S tu b a nd A c ti o n S t u b de s c r i be d
b e fo re .
C o n d i t i on E n t r y : Th e se re p re se n t the po ss i bi l i ty o f e a c h o f t he co nd i ti o n s tu b
( a n swe r t o e a c h o f t h e co n d i ti o n s tu b ) . Th e c o n d i t i o n e n t r y c an be ` Y ’ fo r Y e s o r
`N’ for No only.
A c t i o n E n t r y : Th e l i st re l a ti n g t o t he se t o f a c t i o n t o b e pe r f o r me d o r t a k e n to
a g i ve n se t o f co n d i t i o n s . Th e a c ti o n e nt r y c an be ` X ’ f o r se l e c ti o n a ct i o n o r ‘ - ‘
f o r u n se l e c te d a c ti o n o n l y .
25
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
T h e f i n a l d e c i s i on t a b l e w o u l d a pp e a r a s b e l o w :
Ta b l e H e ad i n g
D e ci si o n Ru l e ( R 1) D e ci si o n Ru l e ( R 2)
i .e .
a
u ni q u e i .e .
a
u ni q u e
combination
of combination
of
` c o n di ti o n s ’
a nd ` c o n di ti o n s ’
a nd
`actions’
`actions’
C o n di ti o n S tu b :
C o n di ti o n
E n t ry C o n di ti o n
E n t ry
i .e .
if
t he se i .e .
if
t he se
c o n d i ti o n s
e x i st c o nd i ti o n s
e x i st
( Ye s) / n o t
e x i st ( Ye s) / no t
e x i st
(No)
(No)
C1
Ye s / No
Ye s / No
C2
Ye s / No
Ye s / No
C3
Ye s / No
Ye s / No
.....
.....
.....
A c ti o n S tu b :
A c ti o n E n t r y i .e . A c ti o n E n t r y i .e .
t h e n th e fo l l o w i ng t he n the fo l l o w i ng
actions
re su l t a c t i o n s
re su l t
( X ) / n o t re su l t ( -)
( X ) / no t re su l t ( -)
A1
X / X / A2
X / X / A3
X / X / .....
.....
.....
D e ci si o n
(R.....)
Ru l e
C o n di ti o n
E n t ry
i .e .
if
t h e se
c o nd i ti o n s
e x i st
( Ye s) / no t
e x i st
(No)
Ye s / No
Ye s / No
Ye s / No
.....
A c ti o n E n t r y i .e .
t he n the fo l l o w i n g
actions
re su l t
( X ) / no t re su l t ( - )
X / X / X / .....
T y pe s o f D e c i s i o n T a b l e s :
L i m i t e d E n t r y D ec i s i o n T a b l e : Th e C o n di ti o n S tu b s a n d A c ti o n S tu b s ar e
e x h au s ti ve l y de f i n e d . Th i s me an s th a t t he co nd i ti o n e n t r y m a y co n t ai n
e i t he r ` Ye s ’ re p re se n t i n g e x i s te n ce o f c o n d i ti o n o r ` No ’ r e p re se n t i n g n o n
e x i s te n ce o f co n di t i o n . I n t he s a me m a n ne r t he ac t i o n e n t r y m a y co n t a i n
a ` X ’ r e p re se n ti n g e x e c u ti o n o f a p a r t i cu l a r a c t i o n o r ` ─ ’ r e p r e se n t i n g t h a t
p a r t i c u l a r a c t i o n i s n o t to be e x e cu te d .
Illustration.
A c o m p an y a l l o w s c r e di t to i ts cu s to m e r s i f t he y a r e f r o m l o c al
c i ty a n d c a n e i t h e r p r o v i de su re t y o r h a ve g o o d c re di t w o r t hi ne s s .
S t e ps :
1.
I d e n t i f y c on d i t i on s :
L o c a l a re a
:
Ye s / No
P r o v i de s u re t y
:
Ye s / No
G o o d c re di t wo r t h i n e s s
:
Ye s / N o
2.
I d e n t i f y A c t i on s :
R e fu se C re di t
3.
D e t e r m i n e t h e po s s i b l e n u m b e r o f r u l e s . I f th e r e a r e N n u m b e r o f
c o n d i t i on s , t h e r e a r e 2 N n u m b e r o f po s s i b l e r u l e s . I n t h e pr e s e n t c a s e
t h e r e a r e 2 3 po s s i b i l i t i e s . i . e . 8 po s s i b i l i t i e s
4.
D r a w th e t a b l e w it h s t u bs a n d r e qu i r e d n u m b e r o f e n t r y c o l u mn s . i .e .
column for rules.
5.
F i l l t h e c o n d i t i on e n t r i e s u s i n g h a l f r u l e .
6.
F o r e a c h c o lu mn e n t e r t h e c o r r es po n d i n g a c t i o n o r a c t i o n s t o b e
taken.
7.
S c r u t i n i s e th e t a b l e t o f i n d i f a n y o f t h e r u l e s c a n be e l i m i n a t e d .
G r a n t C re d i t
26
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
A L L O W IN G CR E DIT F A C I L I T Y
C O ND I T IO N S :
C 1 : L O C A L C I TY
C 2 : P R O V I D E S U RE TY
C 3 : G O O D C R ED I T W O R TH I N E S S
A C T I O NS :
A1: GRANT CREDIT
A 2 : R E F U S E C R ED I T
D E C I SIO N R UL E S
3
4
5
6
1
2
Y
Y
Y
Y
Y
N
Y
N
Y
Y
N
N
N
Y
Y
X
-
X
-
X
-
X
X
7
8
N
Y
N
N
N
Y
N
N
N
X
X
X
I f w e o b se rve r u l e s 1 & 2 , we fi n d th a t i f C 1 & C 2 a r e `y ’ , i t i s i r re l e v an t
w he the r C 3 i s ` y ’ o r ` N ’ a s i t d o e s no t a f f e c t a c t i o n . So r u l e s 1 & 2 c a n be
c o m b i ne d . A l te rn at i ve l y , r u l e s 1 & 3 c a n be co m bi ne d i n w hi c h c a se C2
b e c o me s i r re l e v a n t.
A g a i n , o bse r ve r u l e s 5 , 6 , 7 & 8 . I f C 1 i s ` N ’ , a c t i o n i s a l w a y s the s a me a n d
i s no t a f f e cte d b y C 2 & C 3 .
A b o ve Ta b l e :
R1
R2
R3
R4
R5
R6
R7
R8
New Table
R1
R2
R3
R4
A L L O W CR E D I T F A C I L I T Y
1
C O ND I T IO N S :
C 1 : L O C A L C I TY
C 2 : P R O V I D E S U RE TY
C 3 : G O O D C R ED I T W O R TH I N E S S
A C T I O NS :
A1: GRANT CREDIT
A 2 : R E F U S E C R ED I T
D E C I S IO N R UL E S
2
3
4
Y
Y
-
Y
N
Y
Y
N
N
N
-
X
-
X
-
X
X
Ex t e n d e d E n t r y De c i s i o n T a b l e :
Th i s i s se c o n d ty pe o f de ci s i o n t a bl e . H e re , the co n di t i o n a n d a c ti o n s tu b
a r e ge ne r al i se d . Th e s t a te me nt s m ad e i n t he s tu b p o rt i o n a re i n co m p l e te .
Th e co n di t i o n a n d a c t i o n e n t r y a r e o f d e sc r i p ti ve ty pe .
I l l u s t r a t i o n : A l i f e i n su r a n ce co mp a n y h a s t he f o l l o wi ng c r i te ri o n fo r
d e c i di ng wh e th e r o r n o t th e i n su r a nce f o r a p e r so n i s t o be a c ce p te d .
I f a pe r s o n ’ s h e a l t h i s g o o d an d the pe r so n i s a ge d b e t we e n 2 0 an d 35
ye a r s , l i ve s i n a to wn o r ci t y , an d i s a m a l e , t he n the p re m i u m c h a r g e d i s
R s . 2 0 pe r th o u s a n d a n d th e po l i cy i s w r i t te n fo r a n a mo u n t n o t e x ce e d i n g
R s . 1 0 , 0 0 , 0 0 0 . I f a pe r s o n s a ti s f i e s a l l the a bo ve c o nd i t i o ns e x ce p t th a t
t he pe rs o n i s a fe m a l e , t h e n the p r e mi u m c h a r ge d i s R s . 2 5 pe r tho u s a n d
a n d t he po l i c y i s w r i t te n f o r n o t m o re t h an R s . 6 , 0 0 ,0 0 0 . I f t he pe rs o n ’ s
he a l th i s po o r a n d t h e pe r s o n i s a ge d b e twe e n 2 0 a n d 3 5 ye a r s , l i ve s i n a
v i l l a ge a n d i s a m a l e , t h e n the p r e mi u m c h a r ge d i s R s . 4 0 pe r t ho u s an d
a n d t he po l i cy i s w r i t te n f o r no t m o r e th a n R s . 2 , 0 0 , 00 0 . I f t h e pe rs o n i s a
f e m a l e , t h e p re m i u m r a te c h a r ge d a n d t he m a x i m u m l i mi t fo r w r i ti n g a
p o l i cy a r e t h e s a m e . I n a l l o the r c a se s , t he pe r so n i s r e fu se d i n su r a n ce .
P r e pa r e a d e c i s i o n t a b l e f o r t h e a b o v e pr o b l e m .
27
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
L I M I T E D E N T R Y D E C I SIO N T A B L E
P O LI C Y O F I NS URA N C E C O M P A N Y
D E C I SIO N
1
2
C O ND I T IO N S :
C 1 : I s h e al t h g o o d?
Y
Y
C 2 : I s a g e be t we e n 2 0 a n d 3 5 y e a r s ?
Y
Y
C 3 : I s t he pe r s o n m a l e ?
Y
N
C 4 : D o e s t he pe rso n l i ve i n to wn o r c i ty ?
Y
Y
A C T I O NS
A 1 : P r e mi u m R s . 20 p e r t h o u s a n d
X
A 2 : M a x i m u m po l i c y a m o u n t R s . 1 0 , 00 , 0 0 0
X
A 3 : P r e m i u m R s . 25 p e r t h o u s a n d
X
A 4 : M a x i m u m po l i c y a m o u n t R s . 6 , 0 0, 0 0 0
X
A 5 : P r e mi u m R s . 40 p e r t h o u s a n d
A 6 : M a x i m u m po l i c y a m o u n t R s . 2 , 0 0, 0 0 0
A 7 : R e fu se i n su r an ce
E X T E N D E D E N TRY D E C I S IO N T A B LE
P O LI C Y O F
D E C I SIO N R UL E S
I N S UR A N C E CO M P A N Y
1
2
3
C O ND I T IO N S :
C 1 : H e a l th
Good
Good
Poor
C 2 : A ge
20 to 35
20 to 35
20 to 35
C 3 : Se x
Male
Fe m a l e
-C 4 : P l a ce o f Re si de n ce
To w n / ci t y
To w n / ci t y
V i l l age
A C T I O NS
A 1 : P r e mi u m pe r
Rs.20
Rs.25
Rs.40
t h o u s an d
A 2 : M a x i m u m po l i c y
Rs.10,00,00
Rs.6,00,000
Rs.2,00,000
amount
0
A 3 : I n s u r a nce Po l i c y
ALLOW
ALLOW
ALLOW
28
R UL E S
3
4
N
Y
-N
E
L
S
E
X
X
-
X
4
E
L
S
E
REFUSE
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
(i)
(ii)
(iii)
( i v)
M ix e d e n t r y d e c i si o n t a b l e
Th i s i s th i r d t y pe o f de ci si o n t a b l e . It u se s the te c h ni q u e s o f bo th a
l i m i te d e n t r y de ci s i o n t a bl e an d e x te n de d e nt r y de c i s i o n t a b l e . Wh i l e th e
l i m i te d a n d e x te n d e d e n t r y f o r m s ca n be m i x e d wi t hi n the t a b l e , o n l y o n e
f o r m m a y be u se d wi t h i n a co nd i t i o n s t a te me n t /e n t r y o r a n a ct i o n
s t a te me n t /e n t r y .
Illustration:
A wh o l e se l l e r h a s t h re e c o m mo d i ti e s t o se l l an d h as th r e e
t y pe s o f c u st o me r s. Th e d i s co u n t i s gi ve n a s pe r f o l l o w i n g r u l e s :
F o r G o vt . o r de r s , 1 5 % di s co u n t i s gi ve n i r re s pe c ti ve o f t he v a l u e o f th e
o r de r .
F o r o r de r s o f m o re th a n R s . 2 0 , 0 0 0 , a n a g e n t ge t s a d i s co u n t o f 2 0% a n d
t he re t a i l e r 1 5 % re s pe ct i ve l y .
F o r o r de r s o f v a l u e be twe e n R s . 1 0 , 00 0 a n d R s . 2 0 , 0 0 0 , a g e n t ge ts d i s co u n t
o f 1 5 % a n d t h e re ta i l e r g e t s 1 0 % .
F o r o r de r o f v a l u e l e s s th a n R s .1 0 , 0 0 0 , t he a ge nt a n d re t a i l e r g et
d i s co u n t o f 1 0 % a n d 5 % re s pe c t i ve l y.
Th e a b o ve r u l e s d o n o t a p p l y to f u r n i tu re i te m s . H o we ve r , i n c ase o f
f u r n i tu re i te m s , a f l a t r a t e o f 1 0% d i s co u n t i s a d mi ss i bl e to a l l t y pe o f
c u s to me r s .
P r e p a re a m i x e d e n t r y de ci si o n t a b l e .
M IX E D E N TR Y D EC I S IO N T A B L E
Decision Rules
D i s c o un t
po l i c y
Conditions
C1: Order
value
C2:
customer
type
C3:
Product
Actions
Discount
A1: 5%
A2:10%
A3: 15%
A4: 20%
1
2
3
4
Any
amount
Any
amount
Any
Govt.
Agent
Retailer
Furniture
Others
Others
Others
More than
Rs.20,000
5
6
Between
Rs.10,000 &
Rs.20,000
Agent
Retailer
Others
7
8
Below
Rs.10,000
Agent
Retailer
Others
Others
Others
X
X
X
X
X
X
X
29
X
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
1.
2.
3.
4.
5.
6.
7.
1.
2.
3.
B e n e f i t s o f D e c i s io n T a b l e s :
F o l l o wi ng a r e g i ven s o me o f t he Be ne fi t s o f D e ci s i o n T a b l e s :
E a s y t o D r a w – D e c i si o n Ta b l e s a re e a sy to d r a w a n d m o d i f y a s c o m p are d
t o f l o w ch a r t s .
C o m pa c t D o c u m e n t a t i o n – Th e d o c u me n t a t i o n i n the fo r m o f de ci si o n
t a b l e s i s co m p a c t s i n ce o n e de ci si o n t a b l e m a y r e p l a c e fe w p a ge s o f a
f l o wc h a r t
S i m pl i c i t y – I t i s e a si e r t o fo l l o w a p a r t i c u l a r p a t h i n o ne co l u mn o f a
d e c i s i o n t a bl e t h an i t i s to go t h r o u g h se ve r a l p a ge s o f t h e f l o wc h a r t s .
D i r e c t C o d i f i c a t i o n - Th e de c i s i o n t a b l e s c a n be d i r e c tl y co de d i n to a
program.
B e t t e r A n a l y s i s – A d e c i si o n t a b l e s h o w s v a r i o u s a l te r n a ti ve s a n d t h e i r
r e s pe c ti ve o u t co m e s s i de by si de f o r b e tte r a n a l ys i s o f t he p r o b l e m .
M o du l a r i t y – Th e co m p l e x p ro b l em s wo u l d re qu i re co m p l e x de ci s i o n
t a b l e s w h i c h c an b e e a si l y b r o ke n do w n to m i c r o - de ci si o n t a b l e s .
N o n - t e c h n i c a l – N o k n o w l e d ge o f c o m pu te r l an gu a ge o r C P U w o r k i n g i s
ne ce s s a r y f o r d r a wi n g de c i s i o n t a bl e s.
L i m i t a t i o n s o f D ec i s i o n T a b l e s
F o l l o w in g a r e g i v e n s o m e o f t h e L im i t a t i o n s o f D e c is i o n T a b l e s :
A l l p r o g r a m me r s m a y n o t be f a m i l i a r w i t h D e c i s i o n Ta b l e s a n d th e re fo re
f l o w ch a r t s a r e mo r e co m m o n
F l o w ch a r t s c an bet te r re p re se n t a si m p l e l o g i c o f t he sy s te m r a t he r th a n a
d e c i s i o n t a bl e .
Th e de ci si o n t a b l e s d o n o t e x p re ss t he t o t a l se qu e n ce o f t he e ve n ts
ne e de d t o so l ve t h e p r o b l e m .
30
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
S O LV ED I LL U S TRA T I O N S :
1.
I f a c u s t o me r h a s g o o d c re di t wo r t hi ne s s an d i n a d di ti o n e i t he r he h a s n o
o u ts t a n di n g l o an o r h e c a n p ro vi de a s u re ty , he c a n be g r a n te d a l o a n by
t he B a n k .
S c r u ti ny f o r L o a n
C o n d i t i on s
G o o d C re di t W o r th i n e s s
O u ts t a n di n g L o an
P r o v i de S u re t y
Actions:
G i ve L o a n
R e fu se Lo a n
2.
1
2
3
4
Y
Y
Y
Y
Y
N
Y
N
-
N
-
X
-
X
X
-
X
W h i l e i nv o i ci n g e a c h c u s t o me r , t he c l e r k h a s t o wo rk o u t the d i sc o u n t
a l l o w a bl e o n e ach o r de r . A n y o r de r a b o ve R s . 2 0 , 00 0 a t t r a c t s a b u l k
d i s co u n t o f 8% . A c u s to me r w i th i n the t r a de i s a l l o we d 1 0 % . The re i s a l s o
a s p e c i a l di s co u n t o f 5 % a l l o we d f o r a n y c u s to me r w ho h a s be e n o r de r i n g
r e gu l a r l y f o r o ve r 5 y e a r s .
D i s co u n t P r o ce s si n g
1
2
3
4
5
6
7
8
C o n d i t i on s
O r de r v a l u e - mo re t h a n R s . 2 0 , 0 0 0
Y
Y
Y
Y
N
N
N
N
C u s to me r wi t h i n th e t r a de
Y
Y
N
N
Y
Y
N
N
C u s to me r o r de r i n g r e g u l a r l y f o r o ve r 5 Y
N
Y
N
Y
N
Y
N
ye a r
Actions:
D i s co u n t – N I L
X
D i s co u n t – 5 %
X
D i s co u n t 8 %
X
D i s co u n t – 1 0 %
X
D i s co u n t - 1 3%
X
D i s co u n t – 1 5 %
X
D i s co u n t - 1 8%
X
D i s co u n t - 2 3%
X
31
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
3.
a.
b.
c.
d.
e.
A co m p a n y o f f e r s h i re - p u r ch a se f i n a n ce whe re t he c u s t o me rs g e t th e
c r e di t f a c i l i ty i f t h e y s a t i s f y a n y o f t he f o l l o wi ng c o n d i t i o n s : Th e c u st o me r mu st h o l d t h e p re se n t j o b f o r mo re t h an 5 ye a r s a n d re s i de
i n t he s a me p l a ce f o r a t l e as t 3 ye ar s . I n su ch c a se he w o u l d ge t c re di t
u p to R s . 1 0 0 0 0 / Th e mo n th l y s a l a ry o f cu s to me r m u s t e x ce e d Rs . 5 0 0 0 a n d mu s t h o l d th e
p r e se n t j o b f o r m o r e th a n 5 ye a r s . I n t hi s c a se t he c re di t w o u l d be g i ven
u p to R s . 1 5 0 0 0 .
Th e mo n th l y s al a r y e x ce e d s Rs . 5 0 0 0 a n d re si de a t the s a me pl a ce a tl e a st
f o r 3 y e a r s , h e i s a l l o we d a c r e di t o f R s . 2 0 , 0 0 0 .
I n c a se t h e c u s t o m e r ’ s m o n t hl y s al a r y e x ce e d s R s . 5 00 0 a n d he ho l ds th e
p r e se n t j o b f o r mo re t h an 5 ye a r s a n d a l so he re si de s a t the s a me p l a ce
a t l e a s t f o r 3 y e a r s, t h e c re di t f a c i l i ty i s a l l o we d u p to Rs . 2 5 , 0 0 0 .
F o r a l l o t h e r cu s to m e r s , re q u e s t f o r c r e di t f a c i l i ty i s re j e c te d .
H i re - P u r ch a se F a ci l i t y
C o n d i t i on s :
C u s to me r h o l ds j o b f o r m o r e t h an 5 ye a r s
R e s i de a t s a me pl a ce f o r a t l e a s t 3 yea r s
M o n t hl y s al a r y e x ce e d R s . 5 0 0 0
Actions:
G i ve C re d i t - R s . 1 0 ,0 0 0
G i ve C re d i t - R s . 1 50 0 0
G i ve C re d i t - R s . 2 0 ,0 0 0
G i ve C re d i t - R s . 2 50 0 0
R e fu se C re di t
4.
1
2
3
4
5
6
7
Y
Y
Y
Y
Y
N
Y
N
Y
Y
N
N
N
Y
Y
N
Y
N
N
N
-
X
X
X
X
X
X
Th e nu me r i c al s co re s i n a n e x a m i n a t i o n ( 0 to 1 0 0 ) a r e t o
i n to l e t te r g r a de s ( A t o D ) u s i n g the f o l l o w i n g p ro ce du re : N u me r i c al S co re
L e tte r G r a de
L e s s t h an 4 0
D
40 to 55
C
55 to 85
B
M o re th a n 8 5
A
S t u de n ts G r a d i n g
1
C o n d i t i on s :
L e s s t h an 4 0
Y
40 to 55
55 to 85
Actions:
L e tte r g r a de -A
L e tte r g r a de - B
L e tte r g r a de - C
L e tte r g r a de -D
X
32
X
be c o n ve rte d
2
3
4
N
Y
-
N
N
Y
N
N
N
X
X
X
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
5.
A f i r m ke e p s de t ai l s o f th e bi l l s r a i se d o n c u s t o me rs i n a c o m pu te r f i l e .
Th e re co r d h a s f o l l o w i n g d a t a f i e l d s :
C u s to me r n a me , Ty p e ( D e al e r / O the r) , B i l l n u m be r , B i l l d a t a , A m o u n t ,
D a te o f P a y me n t .
I f a C u s t o me r p a y s t h e b i l l w i th i n o ne m o n t h , he i s a l l o we d 1 0% d i sc o u n t .
I f he p ay s w i t h i n 1 t o 2 mo nt h s , no d i s co u n t i s a l l o we d . I f he p a y s a f te r 2
m o n th s , pe n a l i n te re s t 1 0% a s ch a r g e d f r o m h i m . I f t he cu s to me r i s a
d e al e r , t h e n th e co r r e s p o n di ng d i s co u n t & i n te re st r a te s a r e 1 5 % , 0 , 1 0 %
r e s pe c ti ve l y .
D i s co u n t / i n te re s t p r o ce ss i n g
C o n d i t i on s
C u s to me r i s a de a l e r
P a y s t he bi l l w i th i n o n e m o n t h
P a y s b i l l i n 1 - 2 mo n th s
Actions:
D i s co u n t - Ni l
D i s co u n t - 1 0%
D i s co u n t - 1 5%
P e n a l I n te re s t - 1 0%
6.
1
2
3
4
Y
Y
-
N
N
N
Y
-
N
Y
X
X
X
X
A Co m p a n y p r o v i d e s h o me de l i ve ry f o r i t s p ro du c ts a n d bi l l s de l i ver y
c h a r ge s a c co r d i n g t o t h e di s t an ce a n d the a mo u n t o f t he bi l l . I f th e
d i s t a nce o f cu s to m e r a n d c o m p an y ’s o f f i ce i s l e s s th a n 5 K M , n o de l i ve r y
c h a r ge s a re l e v i e d. I f t h e di s t a nce i s m o r e t h an 5 K M bu t l e s s t h a n 1 5 KM ,
t he de l i ve r y c h a rg e s a re 2% o f t he b i l l a mo u n t . H o we ve r , i f th e bi l l
a m o u nt i s m o re th a n R s . 1 0 0 0 t he n a c o nce ss i o n al r a t e o f 1 % i s l e vi e d . I f
t he di s t a n ce i s mo re t h an 1 5 KM , t he de l i ve r y ch a r ge s a r e 5% bu t i f th e
b i l l a m o u n t i s m o r e th a n R s . 1 0 0 0 / - t he n 2% de l i ve ry ch a r ge s a re l e vi e d .
D e l i ve ry C h a r g e s pr o ce ss i n g
1
2
3
4
5
C o n d i t i on s :
D i s t a n ce - Le s s t h an 5 K M
Y
N
N
N
N
D i s t a n ce -M o re th a n 5 K M b u t l e ss t ha n 1 5 K M
Y
Y
N
N
B i l l A mo u n t - U p to R s . 1 0 0 0
Y
N
Y
N
Actions:
D e l i ve ry C h a r g e s - N I L
X
D e l i ve ry C h a r g e s - 1 %
X
D e l i ve ry C h a r g e s - 2 %
X
X
D e l i ve ry C h a r g e s - 5 %
X
-
33
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
7.
A F i n a n ce C o m p an y p r o v i de s l o a n s f o r b u i l d i n g re si de n t i al ho u se s o r f o r
p u r c h a si n g ve h i c l e s a n d o the r k i nd o f l o a n a p p l i ca t i o n s a r e re j e cte d
s t r a i g ht a w a y . Th e h o me l o a n o r ve hi c l e fi n a nce a p p l i c a n t s mu s t be
se r v i n g i n G o v t . o r P u b l i c Li m i te d Co m p a n y a n d h a ve g o o d c re d i t r a t i n g .
F a t he r , a l l h o me l o a n a p p l i c a nt s m u s t h a ve c o m pl e ted a t l e a s t 5 y e a r s o f
r e gu l a r se r v i ce , h a v e a b a l an ce se rvi ce o f a t l e a s t 1 5 ye a r s a n d h a ve a l i f e
i n su r a n ce po l i c y b a c k u p . Th e ve h i c l e l o an a p p l i c a n ts m u s t h ave
c o m p l e te d a se r vi ce o f a t l e a s t 3 ye a rs , h a ve a b al a n ce se r v i ce o f a t l e a s t . 7
ye a r s a n d m u s t h a ve a v a l i d d r i v i n g l i ce n ce .
P r e l i mi n a r y S c ru t i n y o f L o an a p p l i c at i o n s
1
2
3
4
C o n d i t i on s :
Se r v i ce i n G o v t . o r P u b l i c L i mi te d Co m p a n y
Y
Y
Y
N
G o o d C re di t R a t i n g
Y
Y
N
A p p l i c a ti o n f o r H o m e L o an
Y
N
Actions:
G o to H o me L o an Ta b l e
X
G o to Ve h i cl e L o a n Ta b l e
X
R e j e ct a p p l i c a t i o n
X
X
H o me Lo a n S c r u ti n y
C o n d i t i on s :
C o m p l e te d m i n i mu m 5 y e a r s o f se r vi ce
B a l a n ce se rv i ce o f m i n i mu m 1 5 ye a r s
H a ve a L i fe I n su r a n ce Po l i c y b a ck u p
Actions:
A c ce p t a p p l i c a ti o n
R e j e ct a p p l i c a t i o n
V e h i cl e Lo a n S c ru t i n y
C o n d i t i on s :
C o m p l e te d m i n i mu m 3 y e a r s o f se r vi ce
B a l a n ce se rv i ce o f m i n i mu m 7 ye a r s
H a ve a v a l i d d r i vi n g l i ce n ce
Actions:
A c ce p t a p p l i c a ti o n
R e j e ct a p p l i c a t i o n
34
1
2
3
4
Y
Y
Y
Y
Y
N
Y
N
-
N
-
X
-
X
X
X
1
2
3
4
Y
Y
Y
Y
Y
N
Y
N
-
N
-
X
-
X
X
X
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
DATABASE MANAGEMENT SYSTEMS (DBMS)
A d a t a b a s e i s a c o l l e ct i o n o f l o g i ca l l y re l a te d i n f o r ma t i o n .
D a t a b a se M a n a g em e n t i s t h e t a sk o f m a i n t ai ni ng d a t a b a se s so th a t
i n f o r m a t i o n i s re ad i l y a v a i l a bl e . M an a ge me n t o f d a t a ba s e i n vo l ve s :
- D e f i n i n g s t ru c tu re s f o r d a t a s t o r a ge .
- P r o v i di ng me ch a n i s m f o r d a t a m a n i pu l a ti o n su ch a s a d d i ng , e d i ti n g ,
d e l e ti ng , e t c . t h e d a t a
- P r o v i di ng d a t a se cu r i t y a g ai ns t u n a u t h o r i ze d a c ce s s .
Th e so f t w a re re qu i r e d t o pe r fo r m t he t a s k o f d a t a b a se m a n a ge me nt i s c al l e d
a D a t a b a se M a n ag e me n t S y s te m ( D B M S) . I n s i m pl e te r m s , A co l l e c t i o n o f
p r o g r a m s r e qu i re d t o s t o re a n d re t r i e ve d a t a f r o m a d a t a b a s e i s c a l l e d a
D a t a b a se M an a g e m e n t S y s te m . Th e m a i n o bj e c ti ve s o f a n y D BM S a re t o :
- P r o v i de a n e f f i ci e n t a n d co nve n i e n t e n vi r o n me n t th a t i s u se d to s to re i n ,
a n d r e t r i e ve d a t a f r o m a d a t a b a s e .
- M a n a ge i n f o r m a t i o n a bo u t u se rs wh o i n te r a ct wi t h t he D B M S a n d th e
a c t i vi t i e s t h a t th e se u se rs c a n pe r f o r m o n t he d a t a .
D BM S co nt r o l s th e i n te r a c ti o n be t we e n the d a t ab a se a n d a p pl i ca t i o n
p r o g r a m s p re p a re d b y p r o g r a m m e r s o n o ne h a n d an d be twe e n the d a t ab a se
a n d no n -p r o g r a mm i n g o r a d ho c u se r s o n t he o t he r . I t a l so p r o v i de s
m e ch a ni s m s fo r m a i n t a i n i n g the i n te g ri t y o f s to re d i n f o r m a t i o n , m a n a g i n g
se cu r i t y a nd u se r a c ce s s , b a c ku p a nd r e co ve ry p r o ce du re s .
A D B M S c a n o r g an i ze , p ro ce ss a n d p r e se n t se l e c te d da t a e l e me n t s f r o m th e
d a t a b a se . Th i s c a p a b i l i t y e n a bl e s de c i si o n - m a ke rs to m a k e s pe c i al q u e ri e s
f o r se a r c hi n g d a ta b a s e co n te n ts tha t a r e no t av a i l ab l e i n re gu l a r re po r t s .
F o r e x a m pl e , a d a t a b a se m a y c o n t a i n t he ne t s al a r y o f a l l t he e m pl o y e es o f
t he o r g a ni z a t i o n . Th e re g u l a r re po r t p r e se nt s a l i s t o f t he e m pl o ye e s w i th
t he i r ne t p a y , i n t h e a s ce n di ng o rd e r o f n a me s o r p a y . H o we ve r , i f i t i s
d e s i re d t o g e n e r a te a l i s t o f e m p l o ye e s d r a w i n g a s a l a ry i n e x ce ss o f R s . 50 0 0
o u t o f t he to t al , t h e a n swe r wo u l d b e p ro v i de d by po s i n g a s pe ci a l qu e r y
t h r o u gh t he D B M S .
W h i l e m a i n t ai n i n g a u n i fi e d d at a b a se t he y c a te r to t he di f f e r e n t
r e q u i re me n t s o f t h e se di f f e re n t u se rs. Th i s i s m a de po ss i bl e by t he D B M S b y
p r o v i di ng two ` vi e w s ’ o f t h e d a t a b a se i .e . a Ph ys i c al vi e w a nd a Lo gi c a l vi e w .
Th e ph ys i c a l vi e w de a l s wi t h a c tu a l p hy si c a l a r r a n ge me n t an d l o c a t i o n o f
d a t a i n t he st o r ag e de vi ce s . Th e l o gi c a l vi e w o r t he u se r ’ s vi e w i s th e
r e p re se n t a ti o n o f d a t a i n a fo r m wh i ch i s me a ni ng fu l t o t he u se r . W h i l e
t he re c an be o n l y o n e p h y si c a l v i ew o f the d a t a b a se, t he re c an be e n d l e ss
n u m be r o f l o g i c al v i e w s , o n e s pe c i f i ca l l y su i t a b l e fo r e ve r y i n di vi d u al u ser .
35
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
F un c t i o n s o f D BM S
A D B M S pe r f o r m s t h e f o l l o w i n g s e rv i c e s : 1.
T r a n s a c t i o n pr o c e s s i n g : A t r a nsa c t i o n i s a se qu e nce o f d a t a b a se
o pe r a t i o n s t h a t r e p re se n t s a l o g i ca l u ni t o f w o r k . I n o t he r wo r d s , i t
r e p re se n ts a c ce s si n g a d a t a b a se r e co r d a n d u p d at i o n , m o di f i c a ti o n ,
d e l e ti o n e tc . t h e re o f .
2.
C o n c u r r e n t M a n ag e r : A D B M S a c ts a s a c o n c u r re n t m a n a ge r w h o se
f u n c ti o n i s t o c o - o r d i n a te t he a c ti o ns o f d a t a b ase m a ni p u l a t i o n p r o ce sse s
o pe r a t i n g c o n cu r r e n t l y w h i l e m ai n ta i n i n g t he c o n si s te n cy o f the sh a re d
d a t a a t t h e s a me ti me .
3.
R e c o v e r y : Th e re c o ve ry me c h an i s ms bu i l t i n to D BM S e n su re th a t th e
d a t a b a se i s re t u rn e d to a co ns i ste n t s t a te a f te r a t r a n s a c t i o n h a s f a i l e d
o r h a s be e n a b o r te d .
4.
S e c u r i t y : S e c u r i ty re fe r s to p r o te c t i o n o f d a t a b ase f r o m a c ce s s b y
u n au t ho r i ze d u se rs . Th e se cu r i ty l e ve l s c an be v a r y i n g f o r d i f f e re n t u se rs
p r o v i di ng di f f e re n t a c ce s s p ri v i l e ge s s o th a t t he o pe r a ti o n s pe r f o r m e d are
m o n i t o re d a n d c o n t r o l l e d b y the D BM S a c co r d i n gl y .
5.
L a n g u a g e In t e r f a c e : Th e D BM S p ro v i de s a n i n te r f a ce w he re by t he u se rs
o f d a t a b a se c re a te a w o r ki ng e n vi r o n me nt w i th o u t w o r r yi n g a bo u t th e
p h y si c al i m p l e men t a t i o n . Th i s i s m a d e po s si b l e b y t he d a t a d e fi n i t i o n
l a n gu a ge an d d a t a m a n i p u l a t i o n co mp o ne n ts o f t he D BM S .
6.
D a t a C a t a l o g : D a t a D i c ti o n a r y o r S c he m a co nt a i ns d e s c r i pt i o ns a b o u t
d a t a , r e l a t i o n s h i ps a n d c o n s t r a i n t s w h i ch c a n be e n q u i re d i n to to g e t
i n f o r m a t i o n a bo u t t h e s t r u c tu re o f t he d a t a b a s e .
7.
S t o r a g e M a n a g e r : D B M S p r o v i de a m e c h an i s m f o r t he m a n a ge me n t o f
p e r m a ne n t s t o r a g e o f d a t a . Th e i nte r n a l sc he m a de f i ne s h o w th e d at a
s h o u l d be s to re d b y th e s to r a ge m a n a ge r wh i c h i n te r f a ce s w i t h th e
o pe r a t i n g sy s te m to a c ce ss t he ph ys i c a l s to r a ge .
36
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
C o m po n e n t s of DB M S
A D BM S h e l p s a pr o g r a m m e r to c o nce n t r a te o n the p ro g r a m l o g i c wi t h o u t
w o r r yi n g a bo u t t h e o r g a n i z a t i o n o f d a t a o r l o c a ti o n o f d a t a . A l l t h e d a ta
ne e de d by a n a pp l i c a t i o n p r o g r a m c a n be a cce sse d r e g a r d l e s s o f th e
a c ce s s me th o d , r e c o r d l o c a t i o n o r r e c o r d c o n te n t . M o s t o f t he D BM S u se a
u se r - f r i e n dl y qu e ry l a n g u a g e an d a l s o a re a bl e to i n ter a c t w i th co m m o n l y
u se d hi g h l e ve l l a n g u a g e s . Th e p r i nci p a l c o m po ne n ts o f a D B M S pe r fo r m
d i f f e re n t f u n c ti o n s a s f o l l o w s , a n d f o r m a s y s t e m co l l e ct i ve l y :
1.
D a t a D e s c r i pt i o n M o du l e :
Th e l i n k be t we e n t h e l o g i c a l vi e w a n d t he ph y si c al r e co r d i s c a l l e d as
D a t a D e f i n i ti o n an d t h e l an gu a ge i s c a l l e d a s D a t a D e fi ni t i o n L a ng u a g e . A
d a t a de f i n i t i o n l an g u a g e ( D D L) i s u se d to de f i ne the d a t a b a se co n ce p tu a l
s c he m a . I t de f i n e s w h a t ty pe o f da t a i s i n t he d a ta b a s e an d ho w i t i s
s t r u c tu re d . I n mo s t D BM S , the D D L al so de f i ne s u se r v i e w s an d ,
s o me ti me s , s to r a g e st r u c tu re s .
Th e d a t a de f i n i t i o n o f d a t a b a se o r t he l o gi c a l st r u c tu re i n wh i ch a n
a p p l i c a ti o n p ro g ra m v i e w s a d a t a i s c a l l e d a s S che m a . S che m a a l so
i n cl u de s a n i n di c a t i o n o f t he l o g i c al r e l a t i o n s hi ps be t we e n v a r i o u s
c o m po ne n t s o f th e d a t a b a se . S i nce t he re c a n be m a n y u se r s a n d
a p p l i c a ti o n p r o g ra m s u s i n g the sa m e d a t a b a se , ma n y d i f fe re nt ` u se r
views’ can exist.
Th e s pe ci f i c se t o f d a t a re q u i re d b y e a ch u se r o r e a ch a p pl i c a t i o n i s
c a l l e d a s S u b - s ch e m a .
A l l t he S c h e m a an d S u b - sc he m a a re m a i n t a i ne d & do cu me n te d i n a D a ta
Dictionary.
A l l the d a t a re q u i re me n t s an d t he d a t a de f i n i ti o n s o f a p p l i c a t i o n
p r o g r a m s a re re fe r r e d to D a t a D e sc r i p t i o n M o du l e , w hi c h a n a l y se s th e
r e q u e s ts a n d a c co r d i n g l y t r a n s fe r s co n t ro l to D a t a M an i pu l a ti o n M o du l e.
2.
D a t a M a n i pu l a t i on M od u l e :
Th i s m o d u l e i s u se d wi th hi gh l e ve l l a ng u age s to q u er y t he co nte n t s o f
t he d a t a b a se , s t o r e o r u pd a te i n f o r m a t i o n i n t he d at a b a se a n d de ve l o p
d a t a b a se a p p l i c a t i o n s .
A D a t a M an i pu l at i o n L a n g u a ge ( D M L ) i s u se d f o r s pe ci f y i n g d a t a b ase
retrievals
and
u p d a te s .
DML
can
be
h i g h -l e ve l
( se t - o ri e n te d,
n o n p r o ce du r a l ) o r l o w -l e ve l ( re c o r d -o r i e n te d , p r o c e du r a l ) .
A hi gh - l e ve l D M L c a n be e m be d de d i n a h o s t p r o g r a m m i n g l a ng u ag e , o r i t
c a n be u se d a s a s t a n d - a l o ne q u e r y l an gu a ge . Th e u t i l i ti e s a v a i l abl e
t h r o u gh th e D M L f o r d a t a p r o ce s si ng su ch a s re t ri e v al , s o r ti ng , d i s p l ay ,
d e l e ti o n o f d a t a / r e c o r d a re c o n t a i ne d i n t hi s m o du l e . I t c a n b e f u r t h e r
c l a s si f i e d a s f o l l o w s :
a.
A pp l i c a t i o n d e v e l o pm e n t u t i l i t i e s : Se t o f p r o g r a ms de si gne d to h e l p
d e ve l o p me n t o f a pp l i c a t i o n p r o g r a m s u s i n g the d a t a ba s e . The a p p l i c a t i o n
ge ne r a to r s a u t o ma t i c a l l y p ro du ce d a t a e n t r y s c re e n s , re p o r ts a n d a
m e n u s s y ste m f o r e n d u se r s t o u se .
37
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
b.
c.
d.
e.
H o s t L a n g u a g e In t e r f a c e : Th i s p a r t i s r e s po ns i bl e f o r c o m m u n i c a ti o n
w i th a p p l i c a t i o n pr o g r a m s a n d i n te rp r e ts t he i n s t r u c t i o n s re g a r di n g d a t a
r e q u i re me n t s re ce i ve d f r o m H i g h Le ve l L a n gu a ge a p pl i c a t i o n p r o g r a m s so
t h a t ne ce s s a r y d a ta c a n b e re t r i e ve d .
B a c k u p, A r c h i v e & R e c o v e r y u t i l i t i e s : To o l s to m ak e c o p i e s , r e t r i e ve ,
r e s t a r t , a n d re co ve r t h e d a t a b ase co n te nt s .
R e po r t W r i t i n g u t i l i t i e s : A u se r- f r i e n dl y i n te r f a ce al l o wi ng u se r s t o
c r e a te c u s t o mi ze d r e po r t s wi t ho u t w ri t i n g a n a p p l i c a ti o n p r o g r a m .
N a t u r a l L a n g u a g e I n t e r f a c e o r Q ue r y L a n g u a g e In te r f a c e : U se r s c an
c r e a te , v i e w , m o di f y , a c ce s s d a t a f ro m t he d a t a b a se a n d a l so a s k spe ci a l
q u e s ti o n s re l a ti n g t o t h e d a t a b a se , the a n swe r s o f wh i c h a r e no t a v a i l a bl e
i n t he fo r m a t te d r e po r t s , u s i n g a s i m p l e E n gl i s h - l i ke Q u e ry L a n gu a g e .
Application
Program
Output
1.
2.
3.
4.
Data
Description
Module
Data
Base
Data
Manipulation
Module
Reasons for using DBMS
D BM S a re e x pe n s i ve to c re a te i n ter m s o f so f t w a re , h a r d w a r e , an d ti m e
i n ve s te d . A q u e st i o n i s o f te n a s ke d t h a t w hy D BM S i ns te a d o f d a t a i n f l a t
files
(which
c an
be
e d i te d / m o d i f i e d
using
word
p r o ce ss o r s
or
s p r e a ds h e e t s) . T h e r e a s o n s w h y DB M S a r e pr e f e r r e d o v e r t h e f l a t f il e s
are as follows:
M u l t i pl e u s e r s - M u l ti p l e u se r s o f d a t a a c t u a l l y i m p l i e s m u l t i pl e d at a
u p d a te r s . A D BM S pe r m i ts m u l t i p l e , co nc u r re n t u p d a te s an d / o r
i n se r ti o n s , a n d wi l l g u a r a n te e th a t e a ch t r a n s ac t i o n c o m m i ts wh e re as
t h i s f a ci l i t y i s n o t a v a i l a b l e i n f l a t f i l e sy s te m .
R e d u c e d R e du n da n c y & I n c on s ist e n c y – O ne co py o f d a t a r e d u ce s
r e du n d an cy a n d i n c o n si s te n cy . A D B M S c a n m a n a ge c o n si s te n cy be t te r
a n d c a n e n f o r ce ad d i ti o n a l c o n s t r a i n t s . I n a f l a t f i l e , i t wo u l d be u p to th e
d i s c i pl i n e o f th e u se r s to e n su re t h a t t he i r e di t s d i d no t vi o l a te th e
c o ns i s te n c y o f t h e d a t a b a s e .
C o n f i d en t i a l i t y , pr i v a c y , a n d s e c u r i t y – I n o r de r to p re se r ve th e
c o n fi de n t i al i ty a n d p r i v a c y o f i nd i vi d u al s , a c ce s s t o d a t a i s o f te n
r e s t ri c te d . I n t h e f l a t f i l e mo de l , we c a n u se f i l e -l e ve l se cu r i ty t o p re ve n t
a c ce s s to ce r t ai n f i l e s . A D BM S h o we ve r , h a s f i ne r l e ve l se c u r i t y a n d c an
p e r m i t o r r e s t r i ct a c ce s s to ve r y f i ne - g r a i ne d c hu nk s o f d a t a .
S t a n d a r d s c an be e n f o r c e d – A D BM S c a n m a ke s u re t h a t co m pl e t e
i n f o r m a t i o n i s e n te r e d a b o u t a p a r t i cu l a r f a c t a n d c a n e n f o r ce l i m i ted
t y pe co n s i s te n cy c h e ck s a bo u t t h at i n f o r m a ti o n . B y e n f o r ci ng s t a n d a r d
d u r i ng d a t a i n pu t t h e q u a l i ty o f t he d a t a i n d a t a b a se ca n b e e n h an ce d .
38
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
R e a s o n s f o r n o t u s i n g D BM S
Th e re a re b a s i ca l l y two s i t u a ti o n s w he n the u s a ge o f D a t a b a se
M a n a ge me n t S y s tem s b e co me s a n o pt i o n . Th e f i r s t i s the c o s t f a c t o r . M a i n
c o s ts o f u si n g a D BM S i n c l u de hi gh i n i t i al se t u p co s t , p o s si b l y c o s t o f
e x t r a h a r d w a re , c o s t o f e n te r i n g da t a , c o s t o f t r a i ni n g p e o pl e to u se
D BM S a n d c o s t o f m a i n t a i n i n g D B M S . The se co n d s i tu a t i o ns wh e n a
D BM S m a y be u n n e ce s s a r y i s i f a c ce s s to d a t a b y m u l ti pl e u se rs i s n o t
r e q u i re d a n d d a t a se t i s s m a l l o r i f d a t a b a s e an d a pp l i c a t i o n a re si m pl e ,
we l l - de fi n e d , a n d n o t e x pe c te d to c ha n ge .
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
1.
2.
B e n e f i t s & L im i t a t i o n s o f D BM S
T h e a d v a n t a g e s of a D BM S o v e r t h e c o n v e n t i on a l f i li n g s ys t e m s a r e as
follows:D a t a i nte g r a ti o n a n d s h a r i n g re su l t s i n re du ce d d a t a d u p l i c a ti o n a n d
d a t a r e d u n d a n c y si n ce e ac h l o g i c al da t a i te m i s s to re d i n o ne p l a ce .
Th e D BA u se s se cu r i t y su bs y ste m pr o v i de d b y D B M S t o s pe c i f y a c co u n t
r e s t ri c ti o n s f o r p r e ve n t i n g u n a u t ho r i ze d a c ce s s .
Th e D BM S p r o v i de s pe rs i ste nt st o r a g e f o r p ro g r a m o bj e ct s an d d a ta
s t r u c tu re s w h e re by o bj e c ts su r v i ve t he te r m i n a t i o n o f p r o g r a m e x e c u ti o n
a n d c a n l a te r be r e t r i e ve d .
D BM S pe r m i t s i n fe re n ci n g a n d a c ti o n s u si ng R u l e s . I t h a s t he c a p a b i l i t y
f o r de f i n i n g de d u c t i ve r u l e s f o r i nf e re nc i n g ne w i n fo r m a t i o n f r o m th e
s t o re d d a t a b a se f ac t s .
M u l ti p l e U se r In te r f a c e s a re p r o v i ded t o s a ti s f y u se r s w i th v a r y i n g l e vel s
o f te c hn i c a l k n o wl e dg e .
Th e u se r - f r i e n d l y f e a tu re s o f a D BM S m a ke i t po ss i b l e fo r a n o r di n ar y
p e r so n wi t h m i n i ma l k n o wl e dge o f co m p u te r s & p ro g r am m i n g l a ng u ag e s t o
u se the d a t a b a se .
D BM S h a s t h e c ap a b i l i t y t o re t ri e ve an d u p d a te re l a te d d a t a e a si l y a n d
e f f i c i e n tl y b y re p re se n t i n g co m p l e x re l a t i o ns hi p s a m o ng d a t a .
D BM S m a ke s e n f o r c i n g d a t a i n te g r i ty c o n s t r a i n t s po s si b l e by s pe c i fy i n g a
d a t a t y pe f o r e ac h d a t a i t e m .
A D B M S m u s t p ro v i de f a ci l i ti e s fo r b a c k u p an d re co ve ri n g f r o m h a r d w ar e
o r s o f t w a re f a i l u re s .
Th e c h an ce s o f e r r o r i n d a t a p r o ce s si n g a n d u p d a t i n g ar e m i n i m i ze d .
Th e i n de pe n de n ce o f p r o g r a m s a n d d a t a r e su l t s i n l e sse r r e qu i re me n t f o r
a p p l i c a ti o n p r o g r a m s .
Th e n o n - re c u r r i n g a n d a d - ho c i n fo r m a t i o n re q u i re me n t s a re me t by th e
u se o f q u e r y l a n g u a g e f e a tu re o f t he D BM S
Th e D B M S a d d s t o t h e f l e x i b i l i ty i n de s i g ni ng a nd c r e a ti o n o f u se r s pe ci f i c re po r t s .
Th e i ns t a l l a t i o n o f D BM S i m pl i e s sa v i ng i n s to r a ge s p a ce & o pe r a ti o n
c o s ts .
H o w e v e r , a D B M S h a s i t s o w n s e t of l i m i t a t i o n s .
I n s t a l l a t i o n o f D BM S i s c o m pl e x a nd e x pe n s i ve p r o po s i ti o n a n d c a n be
t a k e n u p by o n l y th o se o r g a ni z a t i o ns w ho se d a t a p r o ces s i n g ne e d s re q u i re
s u ch a s y s te m
D a t a i nte g r a ti o n a n d s h a r i n g i n D BM S i m p l i e s t h a t i t mu s t h ave
a p p r o p r i a te d a t a se cu r i t y & d a t a i n te g ri t y fe a t u re s t o al l o w a c ce s s to
a u t ho r i ze d u se r s o n l y .
39
Prof. Zulesh Dedhia /P.C.C./ INFORMATION TECHNOLOGY
3.
4.
5.
1.
2.
3.
4.
5.
Th e co nve r si o n o f d a t a f r o m c o nve n ti o n a l f i l i n g s y ste m t o D BM S i s a ti me
c o ns u mi n g p r o ce ss .
A D BM S c a n be m a i n t a i n e d by we l l - qu a l i f i e d D a t a B a se A d mi ni s t r a to r
o nl y , w hi ch m a y n o t be a v a i l a b l e i n a l l o r g an i z a ti o n .
D BM S re qu i re di r e c t a c ce s s st o r age de v i ce s an d ad d i ti o n a l p ro ce s so r
c a p a b i l i ti e s , wh i c h m a y i nc re a se t he o r g a ni s a ti o n ’ s i nve s t me n t i n
hardware.
I m pl i c a t i o n s o f Da t a b a s e A p pr o a c h
P o t e n t i a l f o r e n fo r c i n g S t an d a r d s - Th e d a t a b a se a p p r o a c h pe r m i t s th e
D BA to de fi n e an d e n fo r ce s t a nd a r d s a m o n g d a t a b ase u se r s i n a l a rg e
o r g a ni z a t i o n . I t f a c i l i t a te s co m m u n i c a t i o n an d c o o pe ra t i o n a m o n g v a r i o u s
d e p a r t m e n t s a n d p r o j e ct s , a n d u se rs w i th i n t he o r g a ni za t i o n .
R e d u c e d A ppl i c a t i o n D e v e l o pm e n t T i m e - L e ss t i me i s ge ne r a l l y re qu i re d
t o c re a te a n e w a p p l i c a t i o n u s i n g D BM S f a c i l i ti e s .
F l ex i b i l i t y - M o de rn D BM S s a l l o w ce r t a i n ch a n ge s to the s t ru c tu re o f th e
d a t a b a se wi t h o u t a f f e c t i n g the sto re d d a t a a n d e x i st i n g a p pl i c a t i o n
programs.
A v a i l a b i l i t y o f U p - t o - D a t e I n f o r ma t i o n – A l l u se rs c a n i m me di a te l y se e
t he cu r r e n t ( a n d u p - t o - d a te ) d a t a .
E c o n o m i e s of S ca l e – Th i s r e su l t b y r e d u c i n g the a m o u nt o f o ve r l a p
d a t a - p r o ce s si n g .
F i l e M a n a g e m en t S y s t e m V s . D BM S
Th e b i g g e s t l i m i ta t i o n o f t r a d i t i o na l F i l e M a n age me n t Sy s te m i s th e
c o m p l e te i n te r - de p e n de n ce o f f i l e st r u c tu r i ng & s to r i n g w i th A p p l i c a ti o n
s o f t w a re . I t i s de si g n e d to p r o ce ss da t a i n b a t che s and p r o d u ce o u t p u t i n
p r e pl a nn e d fo r m a t s . I f a n y di f f e re n t i n f o r m a t i o n i s r e qu i re d , th a n th e
w ho l e a pp l i c a t i o n p a c k a g e h as t o b e mo di f i e d o r r e -w r i t te n w h i c h i s
a l t o ge the r i n de pen de n t a n d ti me co n s u mi ng t a s k i n i t se l f . The re f o re , th e
c o nve n t i o n al Fi l e M a n a g e me n t Sy s te m s a r e u n a b l e t o p r o v i de the an s wer s
t o c u s to m i ze d qu e r i e s a n d c h an ge d s ce n a r i o u s i n a t i m e l y m a n ne r .
D BM S o n th e o th e r h a n d a re f l e x i bl e bu t co m p l ex s ys te m wh i c h c a n
a c ce s s th e d a t a c o n t ai n e d i n t he da t a b a s e i n a n y wa y a u s e r s pe c i f i es .
D a t a i n te g r a t i o n fr o m se p a r a te f i l e s m a k e s i t po ss i bl e f o r a u se r to c re ate
i n nu me r a b l e re p o rt f o r m a t s w i t ho u t t he a i d o f p r o g r a m m e r s a n d a s k an y
q u e s ti o n re l a ti n g t o t h e d a t a b ase w i t ho u t t he ne e d o f l e a r n i n g
programming language.
T h e f o l l o w in g t a b l e m a k e s a c o m pa r i s o n b e t w e e n t r a d i t i o n a l f i l e
m a n a g e m e n t s ys t e m a n d D a t a b a s e M a n a g e m en t S y s te m .
F i l e M a n age me n t S y s te m
D a t a b a se M an a ge m e n t S ys te m
S u i t a b l e i n s m a l l s y s te ms ( P C b a se d)
S u i t a b l e i n l a r ge sy s te m s ( M ai n f r a m e s )
R e l a t i ve l y i ne x pe n s i v e
C o s tl y
Fe w ` f i l e s ’ wi t h si m p l e s t r u c t u re
M a n y ` f i l e s ’ wi th co m p l e x s t ru c tu re
I n te g ri t y
left
to
a p p l i c at i o n R i go r o u s i n b u i l t i n te g ri t y che ck i n g
programmer
N o d a t a se cu r i ty
R i go r o u s d a t a se cu r i t y
S i m p l e , p r i m i ti ve b a c k u p / re c o ve r y
Complex
&
s o ph i st i c at e d
b a c k u p / re c o ve r y
O f te n si ng l e u se r
M u l ti p l e u se r s
40