Rockwell Automation FactoryTalk Transaction Manager User Guide - Manual (Page 99)

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Creating Transactions
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parameter, right-click and select either Bind Data Point or Bind Null
Value from the menu. A transaction must have all input parameters
bound to it before it can be enabled. Binding a null value to an input
eliminates the need to gather a value from the database.
 Output parameters. These parameters do not require a binding. The
results of the bound value display under the Bound Value column. If an
output parameter is not bound or is bound to a null, the value is ignored
and this column is empty. A procedure must succeed before output
parameters can be returned to the control system. Normally, you bind
outputs to a data point in the control system; upon the successful
completion of a transaction, a value is written from the stored procedure
to the data point.
 Input/output parameters. These parameters are handled as a single
binding unless they are separated using the Separate Input/output
option. This option permits separate data points to be bound to the same
procedure parameter. This implies that the address from which the input
parameter is derived is different from the address to which the output
parameter is written. This also implies that if an input/output parameter
is used only for output, then the input portion can be bound to a null
value. Leaving an input/output parameter bound to a single data point
causes the value to be read prior to executing the procedure and the
output value to be written upon completion of the transaction.
The Microsoft SQL Server RETURN_CODE contains data that can be
bound as an output to a stored procedure. This value is only available if the
procedure executes successfully. A successful return code does not
guarantee a successful transaction as the transaction is not yet complete.
Bidirectional or Unidirectional Transactions With
Transaction Bindings
A bidirectional or unidirectional transaction with a transaction result binding
implements a data value that is written back to the control system; that data
value allows you to determine if the transaction completed successfully. The
control system can then take appropriate action based on the success or