Counting Events Across Multiple Columns Without Full Joins or Concatenation

Performing Aggregation over the Past X Months on a Pandas DataFrame with Start/End Date Ranges and a Random Reference Date

Extracting Primary and Secondary Performers from a Single MySQL 8 Query Using GROUP_CONCAT Functionality

Calculating Mean, Standard Deviation, and Counts in a Single Record Using Conditional Aggregation for High Performance

Joining Tables with Recent Date for Each Row Then Weighted Averaging

Calculating Quartiles in Data Analysis: Methods and Importance

Working with Dates in DataFrames: A Practical Guide to Creating Columns Based on Date