ABAP Code for Update Routine??

Hi ,

i am looking for a sample code for a update rule. I have to look to see in a ods table \bic\AXXX to see if there is a matching Delivery number and if there is, i have to pick a date field(ZDAT2) from that record to populate my ODS field (eg.ZDAT). When i do this , do i have to load a internal table or something like that????if yes, where do i do the loading???

Thank you

Southie