Auto Sequence String Serial Number

[eddyc99]

I'm looking for a solution to create a public variable that when called in a query will automatically assign the last serial number +1, but the query may pull more than one item without a serial number. The serial number is comprised of letters and numbers only.
I'm stumped !!
Thanks in advance for any help.

[dcrake]

Can you share with us the logic behind this and if possible a clear example of what you have and what you want.

David

[eddyc99]

Thanks David,
I have two tables, one (table1) is a complete list of all items with serial numbers (ABC4000001,ABC4000002....ABC5000102). The other table (table2) has some records that exist in table1 but also some new items which do not have serial numbers that I would like to append to table1. I would like append more than one record a time using an append query if possible and at the same time assign a serial number sequenced on the latest serial number.
For example, the new items below were missing a serial number (s/n) but the query would generate the assigned s/n and append to table1.
new item assigned s/n
XTA ABC5000103
XTB ABC5000104
XTC ABC5000105
XT4 ABC5000106
XT1 ABC5000107
I hope I was able to clear up my question a bit. Thanks again!