All 42 questions
Which dbt tests can you use to validate models and source data?
Asked in 5 of 307 interviews · last asked Sep 22 · Concept · Mid-level
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I use dbt’s built-in data tests: not_null, unique, accepted_values, and relationships. I configure these in YAML to check model or source columns. For business rules, I write custom reusable tests or singular SQL tests that return rows that break the rule.
- Use not_null and unique together for primary keys; unique alone does not reject nulls.
- accepted_values checks allowed values; relationships checks that non-null values exist in a referenced column.
- Data tests pass when no failing rows are returned, unless failure thresholds are configured.
- Source freshness checks run separately with dbt source freshness; they check whether source data is recent enough.
What the interviewer checks: The interviewer checks whether you can choose built-in tests and write custom checks for data quality.
Other ways it was asked
- “What data quality tests are available in dbt?”
- “How do you write data-quality tests in dbt?”
- “What data quality tests can you implement in dbt?”
What is dbt, and why would you use it?
Asked in 3 of 307 interviews · last asked Sep 20 · Concept · Junior
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dbt is a tool for transforming data already loaded into a data warehouse or other supported data platform. You define models, usually in SQL, and dbt runs them in dependency order. I would use it to keep transformation logic in version control, reuse code, test data, and generate documentation.
- dbt handles the transformation step of ELT; separate tools usually extract and load the data.
- Models define transformations that dbt builds as views, tables, or other supported forms.
- Model references let dbt track dependencies and choose the correct run order.
- Tests check data rules, such as unique keys, required values, and valid relationships.
What the interviewer checks: The interviewer wants to know whether you understand dbt’s role and how it makes data transformations easier to maintain.
Other ways it was asked
- “What is dbt?”
- “Can you explain what dbt is?”
How would you safely deploy a change to a dbt model that feeds several business reports, and what would you do if the change created duplicate records after release?
Asked in 2 of 307 interviews · last asked Sep 22 · Scenario · Senior
Other ways it was asked
- “How would you deploy a dbt model change safely when the model feeds several downstream reports?”
- “A dbt model feeds several important reports. How would you release a change safely, and what would you do if the change introduced duplicate records after deployment?”
- “When deploying a dbt model change that feeds several downstream reports, what would you test before release, and how would you recover if it produced incorrect results?”
How do incremental dbt models differ from full refreshes, and when would you use each?
Asked in 2 of 307 interviews · last asked Sep 20 · Concept · Mid-level
Other ways it was asked
- “When would you use an incremental model in dbt?”
- “Can you give an example of when an incremental model in dbt is appropriate?”
- “What is the difference between an incremental dbt model and a full-refresh model?”
What is the ref function used for in dbt?
Asked in 2 of 307 interviews · last asked Sep 20 · Concept · Mid-level
Other ways it was asked
- “What is the difference between source and ref in dbt?”
How would you create a custom SQL test in dbt?
Asked once · last asked Sep 20 · Tooling · Mid-level
How would you work with end users to design data models within a medallion architecture using dbt?
Asked once · last asked Jul 16 · Scenario · Senior
What are the best practices for setting up a dbt project for a team that is new to dbt, and how would you go about establishing the project from scratch?
Asked once · last asked Jul 16 · Tooling · Mid-level
How can we configure dbt to run only the sales or marketing models and their dependencies instead of all models?
Asked once · last asked Jul 16 · Tooling · Mid-level
How would you use dbt to implement silver-to-gold transformations in a Databricks-orchestrated data platform?
Asked once · last asked Jul 28 · Scenario · Senior
How do you design dbt gold-layer models, including dimensions, facts, and dataset selection?
Asked once · last asked Jul 28 · Scenario · Senior
What is the difference between Snowflake and dbt?
Asked once · last asked Aug 31 · Concept · Junior
What does it tell you about your testing strategy if a dbt model passes all existing tests but downstream users report incorrect business numbers?
Asked once · last asked Sep 9 · Scenario · Senior
What is materialization in dbt?
Asked once · last asked Sep 14 · Concept · Mid-level
What is aliasing in dbt?
Asked once · last asked Sep 14 · Concept · Mid-level
What are snapshots in dbt?
Asked once · last asked Sep 14 · Concept · Mid-level
How do the intermediate and mart layers work in dbt?
Asked once · last asked Sep 17 · Concept · Mid-level
What is the schema.yml file in dbt, and what can you define in it?
Asked once · last asked Sep 17 · Concept · Mid-level
What is the difference between dbt and Apache Airflow?
Asked once · last asked Sep 20 · Concept · Mid-level
How do you manage testing in dbt?
Asked once · last asked Sep 20 · Tooling · Mid-level
What are the main dbt materialization types, and when would you use each?
Asked once · last asked Sep 20 · Concept · Mid-level
What filters or conditions should an incremental dbt model use to select new or changed records?
Asked once · last asked Sep 20 · Concept · Mid-level
How would you create incremental dbt models in Snowflake? Write the SQL for them.
Asked once · last asked Sep 21 · Write code · Mid-level
When a dbt test fails, how would you roll back or correct the issue while minimizing the impact on downstream data consumers?
Asked once · last asked Sep 22 · Scenario · Senior
An incremental dbt model on Snowflake that used to run in five minutes now takes 45 minutes. How would you diagnose the problem and what optimizations would you consider?
Asked once · last asked Sep 22 · Scenario · Senior
How would you ensure that optimizations to a dbt model do not reduce data freshness or expose partially updated tables?
Asked once · last asked Sep 22 · Scenario · Senior
What is your process when a dbt test fails on a column?
Asked once · last asked Sep 22 · Scenario · Mid-level
How do you use Git to version a dbt project?
Asked once · last asked Sep 23 · Tooling · Mid-level
You are building a dbt model that feeds a Power BI dashboard. What tests and checks would you put in place before allowing business users to rely on it?
Asked once · last asked Sep 23 · Scenario · Mid-level
A data steward says a source value is valid, but a dbt test rejects it and blocks a dashboard update. How would you resolve the disagreement?
Asked once · last asked Sep 23 · Scenario · Mid-level
If a dbt incremental model succeeds but its output table has gained no rows for two days despite new raw records, what would you check first to distinguish a legitimate period without updates from a broken incremental load?
Asked once · last asked Sep 29 · Scenario · Senior
Other ways it was asked
- “If a dbt incremental model reports success but its created table has gained no rows for two days while the raw table has new records, what would you check first, and how would you distinguish a legitimate period without updates from a broken incremental load?”
If several reports need distinct counts of farms served by month, year, and region, would you precompute those counts in dbt or use a Power BI measure, and how would you avoid incorrect totals?
Asked once · last asked Oct 1 · Scenario · Senior
How do you handle slowly changing dimensions (SCD types) in dbt?
Asked once · last asked Oct 2 · Tooling · Mid-level
An incremental model run failed due to duplicate keys in dbt. How do you fix it?
Asked once · last asked Oct 2 · Scenario · Mid-level
How do you optimize a slow-running dbt project?
Asked once · last asked Oct 2 · Tooling · Mid-level
How would you structure a dbt project into layers?
Asked once · last asked Oct 2 · Design · Mid-level
Other ways it was asked
- “Can you take me through the sample architecture of a dbt project? How is a dbt project layered?”
When implementing dbt gold-layer transformations, how do you work with models that are already in place?
Asked once · last asked Jul 28 · Scenario · Mid-level
What is a model in dbt?
Asked once · last asked Sep 17 · Concept · Junior
What is a dbt macro?
Asked once · last asked Sep 22 · Concept · Junior
Is dbt a tool that uses Kimball principles and turns them into SQL?
Asked once · last asked Sep 29 · Concept · Junior
Could you take me through window functions in dbt?
Asked once · last asked Oct 2 · Concept · Junior
What would you use dbt for in a data workflow?
Asked once · last asked Oct 18 · Tooling · Mid-level
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How this list is made
Every question here was asked by a real interviewer in a real job interview that a candidate ran MeetAssist in. After the call, the interviewer's questions are pulled from the transcript. Practice sessions, tests, exams and anything that was not a job interview are dropped.
Questions are rewritten so they make sense on their own: names of people, employers and clients are removed, and speech-to-text mistakes are fixed. Small talk, logistics and questions about one candidate's own résumé are left out. Rephrasings of the same question are merged, and the count is the number of different interviews it came up in.
The interviews come from candidates who use MeetAssist, so they lean towards software, data and AI roles: the shares describe these interviews, not every ETL and Data Pipelines interview. Answers to the most asked questions are written and checked by an editor; a "common mistake" is shown only when reviews of real answers in these interviews show it, with the count.
307 interviews, 169 candidates, Nov 2025 to Oct 2026. Updated every month with new interviews.
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