SQL/MX 3.x Query Guide (H06.22+, J06.11+)

Contents

HP NonStop SQL/MX Query Guide—640323-001

8. Parallelism (continued)

Plan Fragments 8-16

Degree of Parallelism 8-21

Influencing Parallel Plans 8-24

System Default Settings That Affect Parallelism 8-25

Index

Examples

Example 1-1. OR Optimization DDL 1-13

Example 1-2. EXPLAIN statement OPTIONS ‘f’ Output for Query Using

CHECK_CONSTRAINT_PRUNING 1-18

Figures

Figure 1-1. EXPLAIN statement OPTIONS ‘f’ Output for Nested Join With Indexes

LX1 and LX2 From LINEITEM Table 1-11

Figure 4-1. Left Linear and Zig-Zag Trees 4-13

Figure 4-2. Visual Query Planner 4-16

Figure 5-1. Query Plan Output in Visual Tree Format 5-4

Figure 5-2. Group By Operator Not Using DAM 5-11

Figure 5-3. GROUP BY Operator at the DAM Level 5-12

Figure 5-4. Two GROUP BY Operations 5-12

Figure 5-5. Query Tree for the Forced Plan 5-14

Figure 5-6. Logical Specification and Lower Exchange Operators 5-15

Figure 5-7. Type2 Hash Join 5-16

Figure 8-1. Matching Partitions Join Using ESP Parallelism 8-14

Figure 8-2. Serial Hybrid Hash Join Using DAM Parallelism 8-15

Figure 8-3.

EXPLAIN statement OPTIONS 'f' SQLQUERY Output for Sample Query

Using ESP Parallelism 8-18

Figure 8-4. Query Tree With ESP Parallelism 8-19

Figure 8-5. Plan Fragment Boundary 8-19

Figure 8-6. Sample Query Plan Showing Plan Fragments 8-21

Figure 8-7. EXPLAIN statement OPTIONS 'f' SQLQUERY Output for Sample Query

Using DAM Parallelism 8-22

Figure 8-8. Query Tree for Sample Plan Using DAM Parallelism 8-23

Tables

Table 1-1. Valid Queries and Operators for OLT Optimization 1-9

Table 3-1. Histogram Temporary Tables 3-2

Table 3-2. Histogram Statistics Tables 3-3