how to merge 2 databases of 2 similar applications?

how to merge 2 databases of 2 similar applications?

HI

i created an application for data entry.. the serial numbers start from 2500, 2501 and so on...

now i duplicated the same application and added data with serial number 1--- 2400 ..

now i want to merge both as single database..how can i merge 2 databases of similar application carrying serial # 1- 2400 and other from 2500 - 2800?