Creating custom reports means designing reports or dashboards that answer a specific business question, using data pulled, cleaned and modeled from one or more sources. Custom report development skills combine SQL, data modeling, a BI platform such as Power BI or Tableau, and the judgment to turn a vague stakeholder request into a report people trust.
Almost every analytics team has a story about a dashboard that looked right for months and turned out to double count revenue. The visualization layer is usually the easy part. The hard parts are understanding what the requester actually needs, joining data correctly, defining metrics consistently and catching the error before a leader quotes the number in a meeting. Those are the skills a hiring process for BI talent should measure.
Glider AI’s Technical Assessments include data and analytics technologies, so you can test candidates on real report building tasks instead of a list of tools on a resume.
What creating custom reports involves
A custom report is built in stages. Each stage needs a different skill, and candidates are often strong in some and weak in others.
- Requirements: clarify the question, the audience, the decision the report supports and how often it is needed.
- Data sourcing: find the right tables or systems and understand how they relate.
- Transformation: clean, join, filter and aggregate data, usually with SQL or a modeling layer.
- Metric definition: define KPIs precisely so the same number means the same thing everywhere.
- Visualization: choose charts and layouts that make the answer obvious.
- Validation: reconcile totals against a trusted source and test edge cases.
- Delivery and maintenance: schedule refreshes, document logic and handle change requests.
Custom report development skills to look for
These skills predict whether a candidate’s reports will be accurate and actually used.
- Writing SQL that joins, filters and aggregates correctly, including handling duplicates and nulls.
- Building a clean data model with clear relationships.
- Writing calculated measures, for example DAX in Power BI or calculated fields in Tableau.
- Defining metrics precisely and documenting the definitions.
- Choosing visualizations that fit the question and the audience.
- Validating results against a source of truth before publishing.
- Asking clarifying questions when a request is ambiguous.
- Explaining a number, and its limits, to a non technical stakeholder.
Roles that need these skills
| Role | Typical focus | What to test most |
|---|---|---|
| Report developer | Building and maintaining operational reports | SQL accuracy, report logic, refresh and maintenance |
| BI developer | Data models and semantic layers behind dashboards | Data modeling, measures, performance |
| BI or data analyst | Answering business questions with data | Requirements, metric definition, communication |
| Analytics engineer | Transformations feeding reporting layers | SQL, modeling, testing and documentation |
| Finance or operations analyst | Custom reports for a business function | Accuracy, reconciliation, spreadsheet and BI skills |
Report developer interview questions
Pair a few of these with a short hands on task.
- A sales leader asks for “a report on how we are doing.” What questions do you ask before building anything?
- Your revenue total doesn’t match finance’s number. How do you investigate?
- How do you handle a join that creates duplicate rows?
- When would you use a calculated measure instead of a calculated column?
- How do you decide between a table, a bar chart and a line chart for a given question?
- How do you document metric definitions so other analysts use them consistently?
- A dashboard is slow to load. What do you check first?
The best candidates start with the decision the report supports. Candidates who jump straight to chart types tend to build reports that look good and answer the wrong question.
How to assess custom report development skills
Tool trivia doesn’t predict report quality. A practical assessment does.
- Give candidates a small dataset with realistic problems such as duplicates, missing values and inconsistent categories.
- Ask them to answer a specific business question with SQL and a simple report or summary.
- Include a reconciliation step where their total must match a provided figure.
- Ask for a short written explanation of their metric definitions and any caveats.
- Score accuracy first, clarity second and visual polish last.
This approach works whether the team runs Power BI, Tableau or another BI platform, because the underlying custom report development skills are the same. For data heavy roles more broadly, see Glider AI’s guide to enterprise software jobs and skills, and for structuring the overall process, the technical evaluation guide.
How Glider AI helps you hire BI and reporting talent
Glider AI’s Technical Assessments cover 250+ languages and technologies, including data and analytics, with role specific tasks designed to predict on the job performance.
- SQL and data tasks that mirror real reporting work.
- Automatic evaluation and shortlisting of top candidates.
- Playback and in depth skill reports to share with data leaders.
- AI proctoring with 50+ checkpoints to help prevent fraud and plagiarism.
For analyst roles where business judgment matters as much as technical skill, Glider AI’s competency based skill tests can add role specific evaluation alongside the technical tasks.
FAQ
What does creating custom reports involve?
Creating custom reports involves clarifying the business question, sourcing and transforming the right data, defining metrics, building the visualization and validating the results. The report is then scheduled, documented and maintained as needs change.
What skills do you need to build custom reports?
You need SQL, data modeling, experience with a BI platform such as Power BI or Tableau, precise metric definition, data validation habits and the ability to translate stakeholder requests into clear questions. Communication matters as much as technical skill.
How do you test a BI developer before hiring?
Give candidates a realistic dataset and a specific business question, and ask them to produce an answer with SQL and a simple report. Score accuracy, metric definitions and clarity in a proctored assessment rather than relying on tool certifications.
What is the difference between a report developer and a BI analyst?
A report developer focuses on building and maintaining reports and the logic behind them. A BI analyst focuses more on answering business questions and interpreting results. Many roles combine both, so assessments should test technical accuracy and business reasoning.
Is Power BI or Tableau experience required?
Experience with the specific BI platform your team uses helps candidates ramp faster, but the core custom report development skills, SQL, modeling and validation, transfer across platforms. Test the core skills first and platform knowledge second.
How long should a report developer skills test take?
Most report developer assessments take 20 to 60 minutes, enough for a data cleaning task, a SQL question and a short written explanation without overloading the candidate.
Hire people who build reports leaders can trust
The number on the dashboard is only as good as the person who built it. Use Glider AI’s Technical Assessments to test custom report development skills on real data before your next BI hire touches production reporting.