Data Management Solutions Using SAS Hash Table Operations

Chapter 11: Hash Object Memory Management

11.1 Introduction

11.2 Memory vs. Disk Trade-Off

11.2.1 General Considerations

11.2.2 Hash Memory Overload Scenarios and Solutions

11.3 Making Use of Existing Key Order

11.3.1 Data Aggregation

11.3.2 Data Unduplication

11.3.3 Joining Data

11.4 MD5 Hash Key Reduction

11.4.1 The General Concept

11.4.2 MD5 Key Reduction in Sample Data

11.4.3 Data Aggregation

11.4.4 Data Unduplication

11.4.5 Joining Data

11.5 Data Portion Offload (Hash Index)

11.5.1 Joining Data

11.5.2 Selective Unduplication

11.6 Uniform Input Split

11.6.1 Uniform Split Using Key Properties

11.6.2 Aggregation via Partial Key Split

11.6.3 Aggregation via Key Byte Split

11.6.4 Joining via Key Byte Split

11.7 Uniform MD5 Split On the Fly