Distributed Databases - Advanced Database Technology and Design - page 302

accno name balance

100 Anne 2000

123 Bob 300

130 Carla - 200

400 David 0

563 Emily - 5670

888 Fred 30

987 George S c - 90

(a)

accno name balance accno name balance

100 Anne 2000 400 David 0

123 Bob 300 563 Emily - 5670

130 Carla - 200 888 Fred 30

S 1 987 George - 90

S 2

(b)

accno balance

accno name

accno name accno balance

100 2000

100 Anne

100 Anne 100 2000

123 300 123 Bob

123 Bob 123 300

130 - 200 130 Carla

130 Carla 130 - 200

S 1

S 2

400 David 400 0

563 Emily 563 5670

-

accno name accno balance

888 Fred 888 30

400 David 400 0

987 George 987 - 90

563 Emily 563 - 5670

S 1 S 2

888 Fred 888 30

(c)

987 George 987 - 90

S 1 S 2

(d)

Figure 9.3 Distribution of the account relation: (a) single database; (b) horizontal frag-

mentation; (c) vertical fragmentation; (d) hybrid fragmentation.