SQL Server Interview Topic 12: ORM and Raw SQL Balance

This topic checks whether you can work with SQL Server from .NET applications. Full stack developers often use Entity Framework, Dapper, stored procedures, or raw SQL depending on the project.

🎯 Interview Goal

You should be able to explain when to use ORM queries, raw SQL, and stored procedures without sounding one-sided.

Q90. What is an ORM?

Quick interview answer:

An ORM maps database tables to application classes. In .NET, Entity Framework Core is a common ORM. It helps developers query and save data using C# objects instead of writing SQL for every operation.

Study in detail: API Integration - This article connects SQL Server work to backend application code.

Q91. Does using Entity Framework mean we do not need SQL?

Quick interview answer:

No. Entity Framework can generate SQL, but developers still need SQL knowledge to design tables, understand joins, debug slow queries, and review generated SQL. ORM helps productivity, but SQL knowledge protects performance and data quality.

Study in detail: Indexes and Performance and Best Practices and Design - These lessons explain why SQL knowledge still matters.

Q92. When would you use raw SQL instead of ORM?

Quick interview answer:

Use raw SQL when the query is complex, performance-sensitive, report-heavy, or easier to express directly in SQL. For simple CRUD, ORM is often enough. The decision should follow project standards and performance needs.

Study in detail: Advanced Patterns - This article explains practical database patterns used in real projects.

Q93. When would you use a stored procedure from an API?

Quick interview answer:

Use a stored procedure when the database operation is reused, needs multiple SQL steps, or is a complex report. It can also help centralize database logic. But simple API operations may not need stored procedures.

Study in detail: Stored Procedures and Functions - This lesson explains stored procedures and functions clearly.

Q94. What should you check when an ORM query is slow?

Quick interview answer:

Check the generated SQL, selected columns, joins, filters, indexes, and number of rows returned. Also check whether the code loads related data unnecessarily. A slow ORM query is still a SQL performance problem underneath.

Study in detail: Monitoring and Performance and Performance Case Studies - These lessons explain slow query investigation.

Q95. How do you avoid loading unnecessary data?

Quick interview answer:

Select only the columns needed by the screen or API response. Avoid returning entire rows or large related data when the UI does not need it. This improves database, network, and API performance.

Study in detail: Select and Where and API Integration - These lessons show practical data fetching habits.

Practice Before Next Topic

Prepare answers for these scenarios:

1. Simple CRUD with ORM.
2. Complex report with raw SQL.
3. API calling a stored procedure.
4. Slow ORM query investigation.
5. Choosing only required columns.

💡 Beginner Interview Tip

Do not say ORM is always better or SQL is always better. Good developers choose based on clarity, performance, and team standards.