"Asterisk Realtime" Help ......?

Hai all…
we were developing an application using the call files in asterisk realtime and mysql…to making the bulk calls… our idea was to upload a text file and gsm file from a webpage and to make the call by automaticallly adding the context by the query for each file…and our plan was to add the context dynamically in to the table …but it seems to a issue tat for each context we hav to add the switch=> command in the and can invoke a single context…extension.conf…is there any other method tat we can invoke multiple context from a single table…??.. has any one tried this…???..thanks in advance…