1. Database Application Application logic: presentation (input /output)
processing logic
data processing (data validation, error identification)
business rules (those not enforced by DBMS)
data management (identify data for query/transaction, DMBS-level)
storage logic
data storage and retrieval

2. Client-Server Architecture
Types of architecture:
File Server
Two-tier architecture
Three-tier architecture
differ in how the application logic is distributed between different components (client, server)

3. Fat Client

4. Thinner Client
DBMS only on server

5. Thinnest
Clients
DBMS only on the
DB server
Business logic on a separate server

6. Client does not need to know anything about the DBMS
Open Database Connectivity (ODBC) Architecture
Client does not need to know anything about the DBMS
Each DBMS has its own ODBC-compliant driver