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Writing Report Ready Queries

Learn Writing Report Ready Queries for free with explanations, exercises, and a quick test (for BI Developer).

Published: December 24, 2025 | Updated: December 24, 2025

Why this matters

Who this is for

BI Developers, Analytics Engineers, and Analysts who deliver recurring dashboards and need robust, readable SQL outputs.

Prerequisites

Comfort with basic SQL: SELECT, JOIN, GROUP BY, WHERE, HAVING.
Understanding of fact vs. dimension tables and primary keys.
Basic window functions and date functions familiarity.

Learning path

Refresh on SQL joins and aggregation levels.
Practice defining grains and using date truncation.
Drill on avoiding double counting with pre-aggregation.
Add window functions for ranks and percents.
Build a reusable KPI dataset and validate against known totals.

Next steps

Complete the exercises below and run the quick test.
Refactor an existing messy report query following the step-by-step pattern.
Set up a personal SQL snippet library for common report-ready patterns.

Note: The quick test is available to everyone; only logged-in users get saved progress.

Practice Exercises

2 exercises to complete

Instructions

Create a report-ready query with grain = day x channel for the last 7 days using table analytics.orders (columns: order_id, customer_id, order_ts, channel, status, revenue). Requirements:

Include only completed orders in metrics.
Columns: day, channel, order_count, revenue_usd.
Stable ordering by day, channel.
Business-friendly aliases as specified.

Expected Output

day,channel,order_count,revenue_usd
2025-01-10,web,124,15234.00
2025-01-10,app,98,11220.50
2025-01-11,web,130,16002.75
...