Number seq

Can any one tell me how to create number seq based on two fields
Means


A010304

CONCRETE MIXER / ONE BAGGER

A01

ICEPL

A01-ICEPL

A01-ICEPL-001

A010305

CONCRETE MIXER / TWO BAGGER

A01

CMIXR

A01-CMIXR

A01-CMIXR-002

Create automatically if field 3 and 4 is change the create numbers seq

HI Ven Benz

For the better understanding for the NumberSeq . follow the below link

http://pavanidupulapati.blogspot.com/2011/08/creating-number-sequence-for-existing.html