Please enable JavaScript.
Coggle requires JavaScript to display documents.
System Design Considerations (Layers (The Data Access Layer (Code…
System Design Considerations
Layers
The Presentation Layers
The Service Layer
The Business Logic Layer
The Data Access Layer
Connection pooling
Working with database tables directly
Database views
+security
-perfomance issues
Stored Procedures
+Reusing execution plna (cached)
Problems with refactoring
Ability to catch performance problems at early stage
Code generator and ORM frameworks
-not predictable SQL code
-necessety to control transactions - you should be able to explicitly control transaction scope and isolation levels
-due to requirement of cross-platforming, there can be skipped special feachers of certain DB system
parameters should have type of column not a value
Design patterns
Repository pattern
Unit of work patters
Optimistic Cuncurrency
A common way to address these issues is by adding a timestamp column to the database table. SQL Server changes
its value every time a row is modified and, therefore, you can detect if the row has been changed after you loaded it.