SQL/MX 3.2.1 Query Guide (H06.26+, J06.15+)

SQL/MX Operators
HP NonStop SQL/MX Release 3.2.1 Query Guide—663851-003
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ESP_ACCESS Operator
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_ACCESS Operator
The ESP_ACCESS operator is a form of ESP_EXCHANGE operator. An
ESP_ACCESS operator isolates the SEQUENCEGENERATOR operator into its own
ESP process. The SEQUENCEGENERATOR operator is isolated because it updates
the sequence generator table by using a new transaction, and does not use the user
transaction.
The ESP_ACCESS operator appears above the SEQUENCEGENERATOR operator in
the query plan. The parent for this operator is the NEXTVALUEFOR operator, which
can reside in either the master executor or an ESP.
When the NEXTVALUEFOR operator is in the master executor, the ESP_ACCESS
operator defines the process boundary between the master executor and a single ESP
that contains the SEQUENCEGENERATOR operator.
When the NEXTVALUEFOR operator is in an ESP, the ESP_ACCESS operator
defines the boundary between the ESP layers of NEXTVALUEFOR operator and the
SEQUENCEGENERATOR operator.
The description for this operator contains the following:
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