Unpivoting Sales Data for Aggregate Analysis: A Simplified Approach to Complex Sales Data Problems

Retrieving the Highest Value for Each ID in a Query: A Comparative Analysis of Window Functions, Ordering, and Limiting

Using Conditions in Columns with Aggregates and Grouping in SQL

Aggregating Data by Month Overlapping Entities with PostgreSQL

Using Window Functions to Count with HAVING Sum Restrictions in a JOIN without Sub-Queries

Optimizing Record Selection in MySQL for Minimum Date Value While Ensuring Specific Column Values

Optimizing MySQL Queries for Counting Table Entries by Time Groups