Extendible Hashing - Class Example

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Presentation transcript:

Extendible Hashing - Class Example

d1 = local depth d = global depth rec 1 rec 4 splitting bucket rec 1 1 splitting bucket d = 0 record 3 = overflow!! d = 1 rec 2 rec 3 record 5 = overflow!! NEXT

rec 1 rec 4 00 01 rec 2 10 splitting bucket rec 3 d = 2 d1 = 2 d1 = 1 11 01 rec 1 rec 4 rec 2 splitting bucket rec 3 record 7 = overflow!! rec 5 rec 6 NEXT

000 110 d = 3 111 001 010 011 100 101 rec 1 rec 4 splitting bucket record 8 = overflow!! d1 = 3 rec 2 rec 7 d1 = 3 rec 3 rec 5 rec 6 NEXT

NEXT d1 = 3 d1 = 2 rec 1 rec 4 rec 8 000 110 d = 3 111 001 010 011 100 101 d1 = 3 d1 = 2 rec 2 rec 3 rec 5 rec 6 rec 7 rec 9 splitting bucket record 10 = overflow!!

NEXT rec 7 rec 9 d1 = 3 rec 1 rec 4 000 110 d = 3 111 001 010 011 100 101 rec 2 rec 3 d1 = 2 rec 8 rec 11 rec 12 d1 = 3 rec 5 rec 6 splitting bucket rec 10 record 13 = overflow!!

d1 = 4 d1 = 3 d1 = 2 0000 1110 d = 4 1111 0001 0010 0011 1100 1101 0100 0101 0110 0111 1010 1011 1000 1001 rec 1 rec 4 rec 2 rec 3 rec 5 rec 7 rec 8 rec 11 rec 12 rec 14 rec 15 rec 6 rec 10 rec 13