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L3 1;3
L4 2;4
L5 4;10
L6 2;5
L7 6;3

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KOSA

Zadanie 5 lista 6:
5. Sprowadzić do 3PN następujące schematy:
a) R1 = ({A,B,C,D}, {A->C, B->D, AB->CD}),

klucz=AB
nie klucz= CD

AB---->CD
------->A--->C
------->B--->D
3PN

b) R2 = ({A,B,C,D}, {A->BC}),

KLUCZ=AD
NIEKLUCZ=B,C

AD-->A--->BC
3PN

c) R3 = ({A,B,C,D}, {AB->C, AC->D}),

KLUCZ=AB
NIEKLUCZ= C,D

AB----->B
----->C
----->A
----->AC--->D
3PN

d) R4 = ({A,B,C,D}, {AB->C, BC->D})

KLUCZ=AB
NIEKLUCZ=C,D

AB----->C
----->A
----->B
----->BC--->D

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lista 3 :
1.a: select * from D left join C on D.D# = C.D#
1.b: select * from D right join C on D.D# = C.D#
1.c: select * from DC left join C on DC.D# = C.D# and DC.C# = C.C#
1.d: select * from DC right join C on DC.D# = C.D# and DC.C# = C.C#

2.a: select * from r where A = 'a1'
2.b: select * from r where A = 'a1' and C = 'c1'
2.c: select * from r where A = 'a1' or C = 'c1'
2.d: select * from r where A = 'a1' and C = 'c3'
2.e: select A from r
2.f: select A,C from r
2.g: select B from r where A = 'a1' and C = 'c1'
2.h: select B from r where A = 'a1' and not (C = 'c1')

lista 4 :

Zad 1.

a: select * from r inner join s on r.B = s.B and r.C = s.C
b: select * from r left join s on r.B = s.B and r.C = s.C
c: select * from r right join s on r.B = s.B and r.C = s.C
d: select * from r,s

zad 6.
a: select * from r minus select * from r where A=a1;
b: select B,C from r union select B,C from s;
c: ???

lista 5 :

zad 1.

a: R1=(ABC, AB->C), R2=(ABD, AB->D, ABD->A)
b: R1=(ABC, AB->C), R2=(ABD, A->D)
c: R1=(ABC, AB->C), R2=(CBD, BC->D)
d: R1=(ABC, AB->C), R2=(ACD, AC->D)

Para która spełnia założenia to:
A i D

lista 6 :

zad 7

a: R1=(ABC AB->C C->B)
b: R1=(ABCD AB->CD C->AD)
c: R1=(ABCD AB->CD C->A D->B)

lista 7

zad 4
a: R1=(ABCD A->C C->A B->AD)
b: R1=(ABCD AB->CD B->D)
c: R1=(ABCD A->C AC->B B->D)

zad 5

Seta

L3 : 2;4
L4 : 5;6
L5 : 5;7
L6 : 1;3
L7 : 8;3

Rafał

l3: 2;3
l4: 4;3
l5: 11;5
l6: 2;5
l7: 4;2

Aequilibrium

L5 : 2,8
L6 : 6,2
L7 : 8,2

Siwy

Lista 6

zad4

(a)
k=A,C NK=B,D Jest w 3PN

(b)
K=AB NK=C,D
R21=({C,D},{C->D})
R22=({A,B,C}),{AB->C})

(c)
K=A NK=BCD
R21=({B,C},{C->B})
R22=({A,C,D}),{A->D},{A->C})
(d)
K=AB NK=C,D
R41=({C,D},{C->D})
R42=({A,B,C}),{A->C},}),{AB->C})

Vadi

potrzebuje 6zad z 6listy i 7zad z 7listy, ma ktos?

Kuba

potrzeba zad 1 z listy 6 i zad 5 z listy 7

Mardok