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

Parallelism
HP NonStop SQL/MX Query Guide—523728-003
8-15
How to Determine if You Have a Parallel Plan
indicates that two PARTITION_ACCESS nodes are started to access the data in
parallel for the two-way range partitioned table.
A portion of the EXPLAIN output appears next and shows the detail for the two
SPLIT_TOP operators:
Seq_Num: 3
Operator: SPLIT_TOP
Left_Child_Seq_Num: 2
Right_Child_Seq_Num: ?
Cardinality: 5.9717000E+004
Operator Cost: 3.2347381E+000
Total Cost: 2.1504770E+001
Detail Cost: CPU_TIME: 5.697804 IO_TIME: 9.2084682 MSG_TIME: 0
IDLETIME: 0.7 PROBES: 1
top_degree_parallelism: 1
bottom_degree_parallelism: 2
top_num_data_streams: 1
bottom_num_data_streams: 2
bottom_partitioning_function: logphys partitioned(grouping, PAPA
with 2 PA(s), log=exactly 1 partition, phys=range partitioned 2
ways on (([150]equiv(O.O_ORDERKEY))))
Seq_Num: 6
Operator: SPLIT_TOP
Left_Child_Seq_Num: 5
Right_Child_Seq_Num: ?
Cardinality: 9.3210889E+003
Operator Cost: 5.0158596E-001
Total Cost: 5.4755492E+000
Detail Cost: CPU_TIME: 1.2585902 IO_TIME: 2.1397587 MSG_TIME: 0
IDLETIME: 0.7 PROBES: 1
top_degree_parallelism: 1
bottom_degree_parallelism: 2
top_num_data_streams: 1
bottom_num_data_streams: 2
bottom_partitioning_function: logphys partitioned(grouping, PAPA
Figure 8-2. Serial Hybrid Hash Join Using DAM Parallelism
root [8]
hybrid_hash_join [7]
partition access [2] partition access [5]
file_scan ORDERS [1]
file_scan LINEITEM [4]
VST086.vsd
split_top [3]
split_top [6]