Hashing with Buckets. read 1 6+4 = 10.

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Presentation transcript:

Hashing with Buckets

read

1

6+4 = 10

2

Cluster 1: Adams  Coles  Flint Cluster 2: Bates  Dean

The problem is that the home address of dean, which is the head of a cluster, is not free (20)Adams  (20)Coles  (22)Dean  (20)Flint Two clusters Overlapped

3

b >=1, may be more than one slot in bucket

4 Actual Addresses. See next slide Applicable to variable length records

Patterns of records access

Summary : Hashing technique Progressive overflow Other techniques 1.Double hashing 2.Chained progressive overflow 3.Chaining with a separate overflow area 4.Scatter tables Buckets