1. Extendable hashing
M.B.Chandak

2. Extendible hashing
Keys 64
Width
Bits (2)
Bits (3)
288 32
100000 10
100 8
001000 00
001
1064 40
101000
101
120 56
111000 11
111
148 20
010100 01
010
204 12
001100
641 1
000001
000
700 60
111100
258 2
000010
1586 50
110010
110 44
101100
Two bit hash table 00 01 10 11 8
148
288
120
204
1064
700
641 44
1586
258
In above hash table, “00” bucket is
completely occupied.
If new element is to be added is 68
Then 68 mod 64 = 4, binary(4) =
If first two bits are used then 68 is mapped
to bucket “00”, which results in collision.

3. How to handle collision
Keys 64
Width
Bits (2)
Bits (3)
288 32
100000 10
100 8
001000 00
001
1064 40
101000
101
120 56
111000 11
111
148 20
010100 01
010
204 12
001100
641 1
000001
000
700 60
111100
258 2
000010
1586 50
110010
110 44
101100 68 4
000100
The bucket 000 and 001 are added as bucket 00 is full
The bucket 01, 10 and 11 remains same with g=2
000
001 01 10 11
010
011
100
101
110
111
641 8
148
288
120
258
204
1064
700 68 44
1586