Concept questionMedium~7 minEF Core Foundations / 9 of 14

Interview question

When would you drop from EF Core LINQ to raw SQL or a micro-ORM like Dapper?

Know when to use raw SQL or Dapper instead of EF Core LINQ

Explains when LINQ is enough, when raw SQL is clearer, and how to keep raw SQL safe and maintainable.

1Say itAnswer out loud first

2CompareCompare with Core answer

3RefineRefine with Stronger and Advanced

TL;DR

I would use EF Core LINQ for normal CRUD, relationship-aware queries, transactions, and code that benefits from the model. I would consider raw SQL or Dapper for complex reporting queries, database-specific features, carefully tuned SQL, or read paths where the SQL is clearer than the LINQ translation. The boundary needs to be explicit, parameterized, and tested.

Full answer below

Practice focus

ORM boundaries, complex SQL, stored procedures, reporting queries, parameterization, mapping, and maintainability.

Answer first

Answer path

Core answer first, then checkpoints toward a stronger answer.

Start
Core answer
Start here. This is the direct spoken answer to practice first.
Why this question matters
Strong .NET candidates do not treat EF Core as a religion. They can explain when the ORM helps and when a direct SQL boundary is clearer.
I would use EF Core LINQ for normal CRUD, relationship-aware queries, transactions, and code that benefits from the model. I would consider raw SQL or Dapper for complex reporting queries, database-specific features, carefully tuned SQL, or read paths where the SQL is clearer than the LINQ translation. The boundary needs to be explicit, parameterized, and tested.
Checkpoint
Stronger answer
Optional upgrade with examples, trade-offs, and sharper phrasing.
I would not switch just because a query is slow. First I would inspect the generated SQL and plan; sometimes a projection or index fixes it. Raw SQL adds its own costs: mapping, safety, duplication of schema knowledge, and less compile-time help. If I use it, I would keep parameters safe, avoid string concatenation, centralize the query enough to maintain it, and document why LINQ was not the best expression.
Finish
Advanced answer
Optional deeper angle for production judgment and nuance.
In production I would choose the tool by ownership and operational clarity. A hand-tuned report query can be excellent if the team can test it, version it, monitor it, and update it with schema changes. Dapper can reduce overhead for specific read paths, but it does not remove database costs. The mature boundary is pragmatic: EF Core for most application data access, direct SQL where it creates a clearer and safer system.

Review signals

Use these to catch weak phrasing, shallow reasoning, and risky claims.

Common mistakesCandidateCommon mistakesMistakes that weaken the answer or signal shallow understanding.Open details

Details

Using raw SQL before inspecting EF Core generated SQL.
Building raw SQL with string concatenated user input.
Scattering large SQL strings across handlers without ownership.
Assuming Dapper fixes bad database design.

Red flagsCandidateRed flagsSignals that an interviewer may treat as risky.Open details

Details

Cannot explain the trade-off beyond speed.
Ignores parameterization.
Has no testing or versioning plan for raw SQL.
Treats EF Core and Dapper as mutually exclusive identities.

Follow-up prompts

Quick interviewer prompts inside this drill.

Follow-up questionsCandidateFollow-up questionsLikely next questions after the main answer.Open details

Details

Treat these as the next interviewer turn. Answer one out loud, then save the gap in your practice notes.

What makes raw SQL safer here?
How would you test a hand-written SQL query?
When would LINQ still be the better choice?

Continue the section

Next in EF Core Foundations: Global Query Filters

Step 10 of 14

Global query filters in EF Core

Opening drill

Concept questionMedium~7 minEF Core Foundations / 9 of 14

Interview question

When would you drop from EF Core LINQ to raw SQL or a micro-ORM like Dapper?

Know when to use raw SQL or Dapper instead of EF Core LINQ

Explains when LINQ is enough, when raw SQL is clearer, and how to keep raw SQL safe and maintainable.

1Say itAnswer out loud first

2CompareCompare with Core answer

3RefineRefine with Stronger and Advanced

TL;DR

Full answer below

Practice focus

ORM boundaries, complex SQL, stored procedures, reporting queries, parameterization, mapping, and maintainability.

Answer first

Answer path

Core answer first, then checkpoints toward a stronger answer.

Start
Core answer
Start here. This is the direct spoken answer to practice first.
Why this question matters
Strong .NET candidates do not treat EF Core as a religion. They can explain when the ORM helps and when a direct SQL boundary is clearer.
I would use EF Core LINQ for normal CRUD, relationship-aware queries, transactions, and code that benefits from the model. I would consider raw SQL or Dapper for complex reporting queries, database-specific features, carefully tuned SQL, or read paths where the SQL is clearer than the LINQ translation. The boundary needs to be explicit, parameterized, and tested.
Checkpoint
Stronger answer
Optional upgrade with examples, trade-offs, and sharper phrasing.
I would not switch just because a query is slow. First I would inspect the generated SQL and plan; sometimes a projection or index fixes it. Raw SQL adds its own costs: mapping, safety, duplication of schema knowledge, and less compile-time help. If I use it, I would keep parameters safe, avoid string concatenation, centralize the query enough to maintain it, and document why LINQ was not the best expression.
Finish
Advanced answer
Optional deeper angle for production judgment and nuance.
In production I would choose the tool by ownership and operational clarity. A hand-tuned report query can be excellent if the team can test it, version it, monitor it, and update it with schema changes. Dapper can reduce overhead for specific read paths, but it does not remove database costs. The mature boundary is pragmatic: EF Core for most application data access, direct SQL where it creates a clearer and safer system.

Review signals

Use these to catch weak phrasing, shallow reasoning, and risky claims.

Common mistakesCandidateCommon mistakesMistakes that weaken the answer or signal shallow understanding.Open details

Details

Using raw SQL before inspecting EF Core generated SQL.
Building raw SQL with string concatenated user input.
Scattering large SQL strings across handlers without ownership.
Assuming Dapper fixes bad database design.

Red flagsCandidateRed flagsSignals that an interviewer may treat as risky.Open details

Details

Cannot explain the trade-off beyond speed.
Ignores parameterization.
Has no testing or versioning plan for raw SQL.
Treats EF Core and Dapper as mutually exclusive identities.

Follow-up prompts

Quick interviewer prompts inside this drill.

Follow-up questionsCandidateFollow-up questionsLikely next questions after the main answer.Open details

Details

Treat these as the next interviewer turn. Answer one out loud, then save the gap in your practice notes.

What makes raw SQL safer here?
How would you test a hand-written SQL query?
When would LINQ still be the better choice?

Continue the section

Next in EF Core Foundations: Global Query Filters

Step 10 of 14

Global query filters in EF Core

When would you drop from EF Core LINQ to raw SQL or a micro-ORM like Dapper?

Practice focus

Answer path

Why this question matters

Review signals

Follow-up prompts

Continue the section

When would you drop from EF Core LINQ to raw SQL or a micro-ORM like Dapper?

Practice focus

Answer path

Why this question matters

Review signals

Follow-up prompts

Continue the section