I have few doubts:

1. When does we design the Database in a SDLC?
2.Does we develope the entire databse at a time, or does the database evolve according to the development of the s/w?
3.Is Database Modelling=Database Designing=Data Modelling?
4.How much time(approx) does it take for a System Analyst and Designer to design a database for an ERP system to be developed for SME?(there are existing tables, but in dbf files which vague and bulky[not properly normalized])

Plet me know the things,

Regards,

Anil Kumar B

2. According to the development phase database must be desinged and optimized to cater the needs.
3. Those 3 are inter-related.
4. It depends on his/her expertize in database design concepts and knowledge in ERP.