Data Transformation Engine Map Designer Reference Guide

Map Designer Reference Guide
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Chapter 11 - Configuring Bursts
For input card settings that have a FetchAs mode of Burst, the type of input
object (as defined in the Source setting) and the FetchUnit work together to
achieve the desired results.
For example, if an input type is one message, the FetchUnit should be 1. If the
input type is a series of messages, the FetchUnit can be any integer.
♦ When the Source is a File of Messages
When the map is run, the first message in the file is found, and converted as
specified. Consecutive messages in the file are encountered, and converted. And
so on until all of the messages in the file are processed. A burst is identified by the
definition of the input type - a message in this case.
If the target is a file, each message produced by a burst is appended to the same
file. If you define the target as a message queue, each message produced is
placed on the output queue after each burst.
♦ When the Source is a Queue of Messages
Change the source of the input to be a message queue. In this case, fetch the first
message on the queue, convert it to the message, and route it to its target -
which can be a file or another message queue, for example. Then, fetch the next
message on the input queue and process it, and continue to fetch messages one
at a time until the input message queue has no more messages.
Retrieval of data prior to the first burst is specific to the adapter.
Batching Logical Messages
You may process bursts of multiple messages. Under some conditions, this may
improve performance. To do this, the logical input (that is, the type of the input
card) is a series of messages. Then, adjust the FetchUnit to the quantity of
messages to process for a given burst.
Automatic Logical Unit Adjustment: If the input type has one component, the
range maximum is automatically adjusted for that component to match the
FetchUnit. For example, the input type is a group with one component (could be a
series of messages with a range maximum of 10) and the FetchUnit = 20. The
series range maximum is automatically adjusted to 20 when the map runs.