• Learning MySQL By Example
  • Introduction
  • 1. How to Retrieve Data From a Single Table
  • 2. How to Retrieve Data from Multiple Tables
  • 3. Using Functions
  • 4. How to Insert, Update, Delete Data in Tables
  • 5. Summary Queries and Aggregate Functions
  • 6. Working With Subqueries
  • 7. SQL Views
  • 8. SQL Indexes
  • Glossary
  • Index
  • Download
  • Translations
  • 5.2

    Grouping Data

    Using the GROUP BY Clause

    • Group rows based on a column(s) or expression(s).
    • If you use an aggregate function with a GROUP BY clause, the aggregation is calculated for each group.

    Table 1. GROUP BY Function

    Aggregate Function Order of Execution Description



    Groups rows of a result set based on columns or expressions separated by commas.

    Filtering With WHERE And HAVING

    • Notice the order of execution. GROUP BY happens before WHERE but after HAVING.
    • It is possible to use WHERE and HAVING in the same statement. They are not mutually exclusive.

    This content is provided to you freely by EdTech Books.

    Access it online or download it at https://edtechbooks.org/learning_mysql/grouping_data.