ETL Testing Test Cases: 35 Examples and Test Scenarios

Every ETL project needs the same core set of checks: did all the data arrive, was it transformed correctly, is it clean, and does the job behave when things go wrong? This page collects ETL testing test cases you can reuse on almost any pipeline — 35 ETL test cases examples grouped by category, each with how to test it and the expected result.

Use them as a starting checklist, then add cases for the business rules in your own mapping document. New to the topic? Start with what ETL testing is.

ETL Test Case Template

A good ETL test case has the same fields as any test case, plus the data details that make it repeatable:

Data Completeness Test Cases

Data Transformation Test Cases

Data Quality Test Cases

Integrity and Key Test Cases

Incremental Load and SCD Test Cases

Load, Restart and Performance Test Cases

More on each area: data validation in ETL, ETL performance testing and data warehouse testing.

ETL Test Scenarios (High-Level)

Test cases are specific checks; ETL test scenarios are the situations you need to cover. A typical scenario list for a new pipeline:

1. First full load into an empty target.
2. Daily incremental load with inserts, updates and deletes.
3. Source sends duplicates or the same file twice.
4. Source data violates rules (nulls, bad formats, unknown codes).
5. A dimension member arrives after its facts.
6. The job fails halfway and is restarted.
7. Volume spikes to 2–3x normal.
8. Schema change in the source (new, renamed or removed column).
9. Report numbers compared with the warehouse after the load.

Interviewers love these as questions — see scenario-based ETL testing interview questions for model answers.

Worked Example: Turning a Mapping Rule into Test Cases

Mapping rule: load orders from src.orders to dw.fact_orders; exclude cancelled orders; city is upper-cased and trimmed; amount_usd = ROUND(amount * fx_rate, 2).

That one rule gives at least five test cases: count with the cancelled filter (TC01), missing keys (TC02), city transformation (TC07), currency rounding (TC10) and amount totals by day (TC05). The transformation check looks like this:

SELECT s.order_id,
       UPPER(TRIM(s.city)) AS expected_city, t.city AS actual_city,
       ROUND(s.amount * s.fx_rate, 2) AS expected_usd, t.amount_usd AS actual_usd
FROM src.orders s
JOIN dw.fact_orders t ON t.order_id = s.order_id
WHERE s.status <> 'CANCELLED'
  AND (UPPER(TRIM(s.city)) <> t.city OR ROUND(s.amount * s.fx_rate, 2) <> t.amount_usd);

Expected result: 0 rows. More copy-ready queries are in ETL testing SQL queries.

Writing test cases from mapping documents is a core skill in our course, ETL Testing: From Beginners to Advanced, which covers SQL validation, data warehouse concepts and real-time testing scenarios. Preparing for interviews? The ETL testing interview practice tests include scenario-based and SQL questions with detailed answers.

Frequently Asked Questions

What are test cases in ETL testing?

ETL test cases are specific checks that prove data was extracted, transformed and loaded correctly, such as count checks, missing-record checks, transformation rule checks, null and duplicate checks, referential integrity and incremental load checks.

How do you write ETL test cases?

Start from the mapping document. For each target column and rule, write a test case with the source and target, test data, the SQL or steps to run, and the expected result. Add standard completeness, quality and integrity checks for every table.

What is the difference between ETL test cases and test scenarios?

A test scenario is a situation to cover, such as an incremental load with deletes. Test cases are the specific checks within it, such as verifying the deleted row is soft-deleted in the target.

How many test cases are needed for an ETL job?

It depends on the mapping, but most tables need at least the standard completeness, quality and integrity checks plus one test case per transformation rule. Critical financial tables usually get the most coverage.

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Written by

Asim Noaman Lodhi

Certified Google Partner · QA Consultant · 12+ Years IT

QA consultant specializing in ETL testing and data quality. Trained 913+ students to transition into data testing roles through hands-on, real-world instruction.

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