EPAM Systems Interview Questions, Process, and Tips

Solid design principles are a set of guidelines for writing maintainable and scalable code.

• Single Responsibility Principle - each class should have only one responsibility

• Open/Closed Principle - classes should be open for extension but closed for modification

• Liskov Substitution Principle - derived classes should be substitutable for their base classes

• Interface Segregation Principle - clients should not be forced to dep...read more

A trigger is a database object that automatically executes in response to certain events.

• Triggers can be used to enforce business rules or data integrity.

• They can be defined to execute before or after a data modification operation.

• Triggers can be created using SQL statements.

• Examples of events that can trigger a trigger include INSERT, UPDATE, and DELETE operations.