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

SQL/MX Operators
HP NonStop SQL/MX Query Guide—640323-001
7-10
ESP_EXCHANGE Operator
AND table_a.col3 = 1
);
DESCRIPTION
fragment_id ............ 4
parent_frag ............ 0
fragment_type .......... dp2
Scan_Direction ......... forward
olt_optimization ....... not used
olt_opt_lean ........... not used
iud_type ............... cursor_update DETCAT.DETSCH.TABLE_B
lock_mode .............. not specified, defaulted to lock
cursor
access_mode ............ not specified, defaulted to read
committed
columns_retrieved ...... 4
new_rec_expr ........... (OWNER_COUNT assign count(1 ))
begin_key ................ (COL1 = COL1) and (COL2 = COL2)
ESP_EXCHANGE Operator
Exchange Group
An ESP_EXCHANGE operator describes a portion of an execution plan that
redistributes the input data stream. This operator represents an interface between
ESPs, between the master executor and one or more ESPs, or between an ESP
process and a DAM process. For more information about exchange operators, see
Section 8, Parallelism.
The ESP_EXCHANGE operator has one child node. The description field for this
operator contains:
Token Followed by ... Data Type
fragment_id A sequential number assigned to the
fragment. 0 is always the master
executor and 1 is reserved for the
EXPLAIN plan. Numbers 2 to n will be
ESP or DAM fragments.
integer
parent_frag The fragment_id for the parent of the
current fragment. The value is (none)
for the master executor.
integer
fragment_type Master, ESP, or DP2. text
buffer_size Size of message buffer. integer
record_length Number of bytes in the record sent. integer