Data Transformation Engine Database Interface Designer Reference Guide

Chapter 5 - Database Sources and Targets Database Connections and Transactions
Database Interface Designer Reference Guide
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Transactional Control
Scope is one of the settings that may be specified for a source (GET > Source >
Transaction > Scope) or target (PUT > Target > Transaction > Scope) in a
map. For information about Scope settings, refer to the Map Designer Reference
Guide.
Note There is one restriction for Scope. If the value of the SourceRule > FetchAs
setting in an input card is set to Burst, the Scope setting is always Map. The
adapter scope is determined to be Map because the context of the SELECT
statement cannot be maintained after the transaction has been terminated
through a commit or rollback. Therefore, if Burst is the value for the
SourceRule > FetchAs setting in an input card, any value in the Scope setting
as well as any adapter command (-CCARD or -CSTMT) specified in the GET >
Source > Command setting is ignored.
Additionally, the global transaction management functionality is available for
certain adapters by using the Global Transaction Management (
-GTX) adapter
command in the Command setting. For more information about this functionality,
refer to the Global Transaction Management Reference Guide.
Database Connection Management
Connection management results in fewer connections being made to the database,
which may improve performance. The Mercator engine reuses existing connections
whenever possible. With global transaction management for those adapters able
to take advantage of this functionality, connections have an even bigger role in
maintaining data integrity. For more information about global transaction
management, refer to the Global Transaction Management Reference Guide.
There are two situations in which connection sharing occurs:
♦ between cards and maps within a map
♦ between multiple maps running serially within the Event Server