For outbound envelopes, the values used to create the envelopes can come from several sources. Values to the left always override values to the right. For example, if there is value in the trade agreement table, it overrides a value in the trading partner table. If a value exists in the trading partner table, it overrides a value in the trade agreement table.
For inbound envelopes, the values in the envelope are placed in the system variables to the far right.
For some system variables, values may be entered into the system variables via a first-level Before Rule. Values entered in this way override any values previously loaded from the trading partner database or the I/O Rule.
