# Qualification engineering against independent oracles: synthetic exercise worksheet

Curriculum reviewed: 2026-10-25. Use public or synthetic data only.
Do not include client evidence, credentials, private identifiers or raw receipts.

## Goal
reproduce a baseline and correctly fail seeded mismatches against a locked independent expectation set; human review evaluates the explanation as well as the machine result.

## Outcomes
- Author independent scalar/grouped expectations.
- Design negative cases and exact scope.
- Preserve decimal/rounding semantics.
- Diagnose a failing qualification without changing the answer key.

## Synthetic case
Describe a Sales report built from order headers and order lines. State which grain you intend and which independently established expectation you would compare.

## Review each lesson
### 1. Establish oracle independence
Separate expectation authorship and capture from the implementation under test.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 2. Freeze a useful catalogue
Define check identities, coverage, tolerances and business assumptions before acceptance.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 3. Handle precision deliberately
Contrast exact SQL decimals, semantic projections and displayed rounding.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 4. Test groups and context
Cover complete key sets, filter states, nulls and empty results rather than one grand total.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 5. Plant realistic defects
Detect a dropped group, duplicated batch, changed grain and wrong displayed value.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 6. Investigate without moving the goalposts
Use receipt supersession, strict evidence and explicit correction/refreeze policy.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

### 7. Defend the claim
Present scope, results and limits to an independent assessor.
Expected output: a written explanation naming the observation, its scope and its limits.
Your notes:

## Failure case
Generated definitions exist but a required execution observation is missing. Explain why qualification cannot pass and name the next required observation. Do not fabricate a receipt or change a frozen expectation.

## Evidence table
| Claim | Expected observation | Available evidence | Missing/stale | Next owner/action |
| --- | --- | --- | --- | --- |
| | | | | |

## Limitations
This worksheet is a completion check, not live qualification, business acceptance or a professional award. Pro assessment and certification policy remain planned. Keep optional live results in customer-controlled custody.