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THIẾT KẾ CƠ SỞ DỮ LIỆU PHÂN TÁN

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Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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8/ 9: -57)4%%;:
<<=#$>!9%(#)?@-(#)
&0%1#-&232-%4%/0< 5"A
B@445&C %*D1!07E32-8+/AF57)
G+%:/'H(#)-*
IJ#1K3''7>%07E32-+<%A
5LM+3)&01)48+%N307E32-
8+/O*8%#@<%>1@9%P2!
HA&C#507E32-8+/##!%4&01)48+
%N307E32-8+/@Q2IR*
S+<%>+N%0TUV*V*WTFAB1&$
3X<%%@YJ#K(*Z%>N%0/@=/#
/[/&$AF8\<%1%-#98K<%"
@]
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 1
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
^_`^MaIbcUd^UDe^_fg^Uhi^
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 2
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 3
LAN
S2
S1
S3
kVl
kVm
kVn
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
^oh^U

CHƯƠNG I: TỔNG QUAN VỀ CƠ SỞ DỮ LIỆU PHÂN TÁN
I.1. Khái niệm về cơ sở dữ liệu phân tán
Mp#5%?07E32-8+/%407E32-8q#q%4
%q'>/[!$)*'07E32-&C&2
5#[J/'':07E32-'/#[J#BK7;
/*
^"&C/:07E32-8+/7;504
0#95[ %>r0*
^&#BF9 [(%407E32-8+/%4B8C8
507E32-9'$#&C8+@"'%4%%/J*
• '$s32-9%47"4J@4#$58+@-
07E32-8+/#$%4B8C807E32-q@4/B8&F
/#[J/%4%%/J*
• T+/s32-&F'%4#[J58+@-207E32-
8+/#$%407E32-B80t*
I.2. Mô hình về cơ sở dữ liệu phân tán
1lu%Hr8vs95%/:/%"#$G
%c^%W%/:9%4%%#-
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 4
WAN
S2
S1
S3
kVl
kVm
kVn
WS1
WS3
WS2
LAN

S2S1 S3
Back_end
Front_end
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
1nsU"&'&!8G%kc^*^
%4%%#-9 '>wK'32-E2%/*
1mu%Hvs9%4%+%rN/%%
#-*

Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 5
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
I.3. Đặt trưng của hệ cơ sở dữ liệu phân tán
Hệ quản trị cơ sở dữ liệu tập
trung
Hệ quản trị cơ sở dữ liệu phân tán
l* xSNKB8*
x T+  G5  y  T+
r8
x z %  7/    >r
B8
n* N%  @N  4  B8  2  32
-#&01*
m* UN% "7)=
P8*
{* J-GN>r
32-*9%3<"
&/+#r*
|* #}32-32

-8q~32-77)
"
l* xz %7/32-B8*
x%W#[J9%4G5):
r[#53&Cq@4*
n* x4B823&C#
&01q@4*
xJ7"07E32
-8+/
m* DX9G5&=P8
#&-"8N>/
[":32-E+*
{* xIq@4s"&/#}q
@4*
xT+/sr32-8+
/#X8NN%@NJ-
GNurrv*
|* TN@NN%*
•* TN@NN%
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 6
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
•* UN  G!    r8  
>r*
I.4. Ưu điểm của cơ sở dữ liệu phân tán
f %J8p87t'%48%#
4$F8&!!-">/[#[J"&r#-7P8
>!832-#>wK'-"**
^+J%5%3tsI/%/J#32-&C?E2
#[J7#-/F-GNr*

J)GN#N%s -G#-8+
4/@48B#=-8#q):.#[Jq@4*
^+%H4Bs-B88H8%5%@[
W7;%@4-".4*"#$-8+/2&
€•N&E%49%€39&€E%49%91•
9%4%19%9.4/9%/#X4@1&*
^+"4#N‚s-+83"&C32
-$"4B%*"#$-8+/332-8+/
#-''.7<#<#1#B"4>wK32-7;0*^/
32-&C&2/#[J&>'B8Fr397;
N%3,32-8NY'&5*.9N-/ 
N%W'H3q.&3=*
zN‚%8q~s#->r32-8q4#%4%/
%4&"'%*^!9@rƒ%4W179#07E32
-9 &C>r'/#[J[8&002%4&"
9 &C!@E%4&"/9W*
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 7
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
h63%E4s#-8/ G%4:0#[9
&C%4/363@Q/'%#5@4>wK%'%
07E32-#%4F%4#[J%?9 B8B8%5%
4B8#$rF#BK@'3&$*
I.5. Nhược điểm của cơ sở dữ liệu phân tán
z9GNK#s-B8•%4G5 @NN%
%*-8+/#-GNKr"p%#132-E20
//G5/*
4B#J-)7w3qr8sA.+-B8A&C7w
3q+3'94B07#$-8+/*
!4„ #WC…Bs-B8/

r8q8%5%#/WC…BJC8%49*_-8+/
#$5r8/ !C8'JC8*UN
G!#r5?859‚"p%*
z!#1/-8+/@„8H807#$/-B8
'/N&„0@~%N8%5%X8H*
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 8
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
CHƯƠNG II: THIẾT KẾ CƠ SỞ DỮ LIỆU PHÂN TÁN
II.1. Mục đích của thiết kế cơ sở dữ liệu phân tán
D-!!07E32-8+/#-!!-"%%/
J%-07E32-8+/7;'F,8NG![><%32
-#&017;&C?2#[J%%/J*
&C8-"%%/JA97†1#-!!07E32
-8+/95Js
• T+/-GN[07E32-'/F%%/J*
• T+//&01H3q'/-GN[9*
II.2. Các chiến lược thiết kế cơ sở dữ liệu phân tán
II.2.1. Quá trình thiết kế từ trên xuống
8y3‡s8&08/8!!.'>"#&C%5
%W59-%#q'"!8
:#:!!8*
ˆ~%/@&$7s
xT+J'sB8'#532-#>wK:rN%
&97w3qIVh*
x!!1s9-%#q[(3-&3=
"*
x!!/-%sG/1><%>pY 0?IVh*
x!!8+/s!!/&C~/-%q@4@Q/8+
//) /#[J:-"8+/*

x!!#BKs/>/&C~/-%q@47/!@[
&2&0H*
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 9
T+J'
‰'-"
!!/-%
!!1
z/-%q >r
^&C~
!!8+/
^'-
^'-
&C~/-%q@4
!!#BK
&C~#BK
Y#@N1
8N~ 8N~
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
Quá trình thiết kế theo hướngtop-down
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 10
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
II.2.2. Quá trình thiết kế từ dưới lên
!!.'>"JC8#$2IVh!!.*'
)!F?82IVhA97†#-%#q!!
8NJC8F%4IVh*!!.3&$'7;JC81
"*zE %:!!.3&$'//-%&C~q@4*
S/17;@~%#-JC8/&C~q@4&C~/
-%q*

II.3. Tính đúng đắn của phân mảnh
J:u%8<<<77vsIG-@rƒ*UN7w&C8+A
/%N*z9J:'%W%q32-„8N
&C&2l?#%N9*
J/u<7vsIG-@rƒ*UN7w&C8+A
/%Nl****z9J:'LC8O/8+%N:
G-N:32-@:G-*z/-%LC8OE+
/wG-∆7Š∆∀*/w∆Yƒ<.
8+%N*zN‚/!%4G-./%N:9N%@NQ/
@4[(<8q432-7;&C@N*
Ju37‹<77vsIG-@rƒ*UN7w&C8+A
/%Nl****z9J/@-'%4%q32-3
9%4A>r-%N17;>r-%N/*
'ŒN%@N/%N7;/@-*I,8+%N
31/4J/J8N&C?8%W%N#1#BJ
/@-•/83q#$/4J/*
II.4. Cách cách phát phân mảnh
z+@Ns%W%NQ%'%4#[J~@N73r:
%4%N'%
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 11
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
^+@Ns
• ^+@N:s%4%NE%4#[J@407E32-5~
E.#[J
• ^+@N.8s%W%NE##[J
II.5. Các kiểu phân mảnh dữ liệu
II.5.1. Phân mảnh ngang
II.5.1.1. Phân mảnh ngang nguyên thủy
[(s•‹Šσ

Ž‹
•u•vl•‹•‡
D$Ž‹HJC8%<%8<3<*
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II.5.1.2. Phân mảnh ngang suy dẫn
I#$‡<uvŠV#%<%@<uvŠ•/%N&C7
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 12
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc

JFP:8+%N73X
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II.5.2.1. Định nghĩa
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 13
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
I//[7<uG

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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 14
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc

U/[7w3qE@N7s
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 15
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 16
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 17
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 18
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 19
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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’/•%q8&018J• %/”
JIS
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do ’>/[/8+"r”
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Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 20
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
‘sŠxn3‡l3
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until  )-V_Ž&C2
>+3)%B<#[J>'3[

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end.
DJ3q
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 21
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
9s
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 22
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
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u.%BusescSuGv~%24J%G#r!v
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Có hai phương án chia:
Phương án 1:
cŠ ’c
m

ˆcŠ ’c
n
c
{

SŠ ’G
l
” uS~%2#rG%9cSuGv¨¨:cv
ˆSŠ ’G
m
” uˆS~%2#rG%9cSuGv¨¨:ˆcv
šSŠ ’G
n
G

{
” ušS~%2#rG,:S*v
ISŠ {| u.accsM<%S~%2Gs4rN/V3,G9v
IˆSŠ ž| u.accsM<%ˆS~%2Gs4rN/V3,G9v
IšSŠ Ÿ u.accsM<%šS~%2Gs4rN/V3,G9v
Js IS™IˆSxIšS
n
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Phương án 2:
cŠ ’c
m
c
n

ˆcŠ ’c
{

SŠ ’G
l
G
n
” uS~%2#rG%9cSuGv¨¨:cv
ˆSŠ ’” uˆS~%2#rG%9cSuGv¨¨:ˆcv
šSŠ ’G
m
G
{
” ušS~%2#rG,:S*v
ISŠ |œ u.accsM<%S~%2Gs4rN/V3,G9v
IˆSŠ œ u.accsM<%ˆS~%2Gs4rN/V3,G9v

Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 23
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
IšSŠ žŸ u.accsM<%šS~%2Gs4rN/V3,G9v
Js IS™IˆSxIšS
n
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V7/8&0/l#8&0/nr¨IS™IˆSxIšSn¨:8&0l$0
ЧI8&0/l*H%N’c
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c{ œ m ž| žŸ

II.6. Tối ưu truy vấn
II.6.1. Tối ưu truy vấn gồm:
xz1%!%&C><%B8C8:/!&C8&0/
)#r/* '@B/?&:@4"&9F
B8#/+"u‹<<v+/w#$/8p8/"?J
h<7<7*K3#-/#[H)"9N&EGr!-

‚:/#rG-*
xI!&C1%!%&C7w3qG4u3%
8%%v#$Jr0[u3<<%7v*I/!&C>+
3)/8&0/)@P./G-07E"'%5G-
%W@&$!3&C/8&0/N*I!&CG
4>+3)8&0/N<54u@<3‘7v*I,!&C
%‚1>+3)+<57+u3<8‘7v*I/!&C#p
N%@N1%&C/8&0/N#$%48Jr8B&C
7"G-+#r$*
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 24
Bài thu hoạch môn Cơ sở dữ liệu nâng cao GVHD: PGS.TS. Đỗ
Phúc
x1J8J:@4"&9~%9/%8J 3)/
8J://w7"-"'32-07E#/H &$&C
J//J&$!GN*
II.6.2. Các thuật toán tối ưu hóa truy vấn
II.6.2.1. Thuật toán INGRES phân tán
^U•ZV7w3q %"&94%q':B/%
N% 8JYC8:5#/8H*IFKQ
B/"&9#r@€G8J532-!%B!GN
# 0NB/•>p 8+%N*
#+#r&C36N@Q8p8JG-@4u3
Œ4v#&C~~%s %%#J&$:%W
%N*B/&C)-%>r8/:+#r&C
%:umaster sitev*
Thuật toán tối ưu hóa INGRES phân tán (D-INGRES-QOA):
8s•S+#rG-
š8s!GN:#rG-"=
Begin
for %Wš•S


9 /in •Sdo ’rN/#rlG
-”
run (ORQ
i
)
end
MRQ–¢list ©REDUCEuMRQv 
while n ªœdo ’7"+#r F” 
begin
MRQ–©SELECT ¢QUERYuMQR–¢listv
Ž%<x7<x7©SELECT ¢STRATEGYuMRQ–v
’5/%NA$%&C”
Cao Thị Thuỳ Linh – MSHV: CH1101099 Trang 25

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