Informatica triggering

Your question is not very clear. However, if you mean to say that you are loading the same target table using two different mappings, then here is the answer. You can use any one of the below approaches depending on which one suits your requirement

1) If you are sure that both the mappings might pull common records and load them, then modify your SQ or Filter/ router to load mutually distinct data set

2) You can create the second mapping using Insert/ Update/ Reject logic by using the Update strategy transformation. If the record coming from source already exists in target, then reject or update the new row coming based on your requirement. If the record is new, then insert it.

Hope this helps.