Data Transformation Engine Services Guide

Chapter 8 – Using Messaging Adapters
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Within a map, some input cards may be in burst mode while others are in integral mode, meaning that
the cards in integral mode are executed once only.
Burst Mode
Burst mode allows many data inputs to transfer at once, for example in batches. Burst mode is valuable
if you are dealing with large amounts of messages where it would not be feasible to pass all of the
messages in one retrieval due to memory limitations. Burst mode is also useful for consuming multiple
source objects and creating multiple target objects in a single map execution.
When a burst is processed, all messages that were retrieved are concatenated and returned as a single
unit for map processing. The size of the burst is defined with the Map Designer input card
AdapterSource > FetchUnit setting.
Burst mode allows a single input card to retrieve multiple data source objects repeatedly. Therefore a
burst can be considered an iterative data source retrieval. When an input card is set to burst mode, the
messaging adapter, upon each map card execution, returns the number of messages defined by the
FetchUnit setting. The messaging adapter repeats the input card execution until the number of messages
specified with the Quantity adapter command (-QTY) is received.
Integral Mode
Integral mode allows for the receipt of one data input at a time. When an input card is set to integral
mode (InputData > CardMode = Integral), the messaging adapter retrieves messages one at a time
until the number of messages specified with the Quantity adapter command (-QTY) is reached.
The number of messages specified in the FetchUnit setting are retrieved and passed to the Command
Server. FetchUnit has a default value of S, which specifies retrieval of all available objects.
The Quantity adapter command (-QTY) specifies the limit of messages retrieved, regardless of the
FetchUnit setting. If the value specified for the FetchUnit setting is less than the number of messages
specified with the Quantity adapter command (-QTY), the number of messages specified with the
Quantity adapter command (-QTY) are retrieved from the queue. This means that some messages may
be deleted from the queue but not processed. If this occurs, the warning message One or more
messages were removed from the queue but not processed is returned.
If all inputs have a CardMode of Integral, there is a single burst.
For Command Server execution, if there are no messages on the queue, the adapter blocks indefinitely,
or if specified, until the timeout specified with the Listen adapter command (-LSN) has expired. If no
messages meet the criteria before the timeout period expires, the warning message No Messages
were found is returned.
Transaction Commitment
In NonStop DTE, you can define under what circumstances a transaction is committed. Transaction
commitment rules are also referred to as “scope.”
To define transaction commitment behavior, use the AdapterScope settings for a source or target in a
map. The AdapterScope value can be one of: