Definition of Variables in Process Data Requests and Calculation Formulas 
Use
You define variables in process data requests and calculation formulas to transfer the value of a message characteristic to a succeeding process instruction.
Here, you can use the variable for the following, for example:
To define default values and input validations in process data requests
To assign values to message characteristics in hidden data requests
To define calculation formulas in process data calculation formulas
To define export and changing parameters in dynamic function calls
Features
You can define a variable for every message characteristic of a process instruction. The data type of the variable is identical to that of the message characteristic (for example, CHAR or NUM).
Depending on how you define the variable, it is valid:
In the PI sheet in which it has been defined
For the entire process order
To define a variable, you assign one of the following characteristics immediately before the message characteristic in the process instruction:
Characteristic |
Meaning |
Value |
PPPI_VARIABLE |
Variable is valid within the PI sheet |
New variable name (see below) |
PPPI_GLOBAL_VARIABLE |
Variable is valid for the entire process order |
New variable name (see below) |
In general, you can choose any name for a variable. To avoid conflicts with other functions, do not use:
The variable name X
Blanks and arithmetic operators as part of the variable name
The following character strings at the end of the variable name:
_< number > , for example, _1 , _2
_ COUNT
_ SUM
Note
If a variable was defined for the entire process order, the system does not transfer its value to the process instructions of other PI sheets unless it cannot be changed anymore. This is the case after the value has been reported, that is, when the corresponding process message has been transferred to process management to be send to its destination.