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

SQL/MX Operators
HP NonStop SQL/MX Query Guide—640323-001
7-11
ESP_EXCHANGE Operator
The following is an example of the ESP_EXCHANGE operator:
create table tabl3 (a int, b int, c int,d int, e int);
create table tabl4 like tabl3;
create view view30 as
select * from tabl3 union all
select * from tabl3 union all
select * from tabl3 union all
select * from tabl3 union all
select * from tabl3;
create view view40 as
select * from tabl4 union all
select * from tabl4 union all
select * from tabl4 union all
select * from tabl4 union all
select * from tabl4;
parent_processes Indicates the number of processes that
the ESPs in the ESP_EXCHANGE
operator communicate with either
additional ESPs (as indicated by
another ESP_EXCHANGE operator) or
the master process.
integer
child_processes Indicates the number of processes that
supply the ESPs of an operator with
rows. The number of ROWS_OUT
(also called CARDINALITY) from the
operator that supplies the
ESP_EXCHANGE operator with data
indicates how many rows the
ESP_EXCHANGE operator is
expected to receive.
integer
parent_partitioning_function Type of top partitioning and contains
summary information about the parallel
plan.
text
child_partitioning_function Indicates how the input data received
by the ESP_EXCHANGE operator is
organized.
text
merged_order Expression describing sort keys used
to control the interaction between the
parent process (usually the master)
and ESPs when the result is ordered.
expr(text)
bottom_partition_input_values Internal values that identify the part of
the data the ESP will work on.
text
partitioning_expression Expression used to partition data. expr(text)
Token Followed by ... Data Type