SQL/MX 2.x Query Guide (G06.24+, H06.03+)

Hewlett-Packard Company—523728-003
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HP NonStop SQL/MX Query
Guide
Index Examples Figures Tables
What’s New in This Manual vii
Manual Information vii
New and Changed Information vii
About This Manual ix
Audience ix
Organization ix
Related Documentation x
Notation Conventions xii
1. Compiling and Executing a Query
Overview 1-1
How the Compiler Works 1-2
Compilation Steps 1-2
Parsing, Binding, and Normalizing 1-3
Query Plan Caching 1-5
Improving Query Performance 1-6
Factors That Can Affect Compile Time 1-13
How the Executor Processes the Plan 1-14
2. Accessing SQL/MX Data
Access Methods 2-1
Storage-Key Access 2-1
Index-Only Access 2-2
Alternate Index Access 2-4
Full Table Scan 2-5
Understanding Unexpected Access Paths 2-9
MultiDimensional Access Method (MDAM) 2-12
Specifying MDAM 2-12
Comparing MDAM With Single Subset Access 2-13
How MDAM Processes Queries 2-14
Influencing the Optimizer to Use MDAM 2-16