Update Z-table from internal table.

Hi Experts,

I have requirement to update z-table from an internal table.But,If some entries from the internal table exist in z-table then those entries should not get inserted/modified/updated.

I found one solution but it creates performance issue(i think).....

Solution i found::-

Take all records from z-table.

Delete records from internal table which matches above fetched records.

Now,insert remaining records into z-table.

Taking all records from z-table may take huge time.....

What is another feasible solution????

Thanks & Regards,

Abdul