I use 2 tables in my database, table 1 for leads/prospects and table 2 for existing customers - table 1 will be updated on a daily basis by adding leads/prospects - table 2 will be updated on a monthly basis by importing the data from our main system.
My question - how do i display in my form that table 2 is existing customers? Must i add a field in table 2 for this purpose, say "existing_customer = y" or what other options are available? The information of table 2 must be visible on the form for other purposes. Thanks

You really only need one table, in that table you have an indacator that denotes what type of record this is.

P - Prospect
C - Customer
D- Dormant

etc.

Then once you add a person to the tabel you only need to change their status. No need to move them from one table to another.

There is no reason to separate the tables. Combine them and add a field to indicate the status of the record as a lead or customer. Everything will be much easier then.

Thanks, just to make sure - i need to import my whole "customer" base on a monthly basis from our internal system. I will have to add the field before i import? Will this process work in one table?

If you are importing your whole customer base on a monthly basis I would import into a temporary table first then perform an update query on your main table.

What are you using as a primary key?

Thanks again, at this stage i'm trying to establish the correct layout - in my leads/prospects table i'm using a "LeadID" but i'm not to sure how to go about my customers - will you please help me with a layout in order to import/update monthly. Thanks, i really appreciate...