GROUP BY

GROUP BY

The GROUP BY, as the name suggests, sorts rows together into groups. The clause returns one row for each group. Data is organized using a comma separated list of columns as the criteria specified after the GROUP BY clause. The GROUP BY statement is often used with aggregate functions such as COUNT, MAX, MIN, SUM, and AVG to calculate an aggregated stat for each group.

Syntactically, the GROUP BY clause must appear after the FROM and WHERE clauses and is also evaluated after them. However, GROUP BY is evaluated before the ORDER BY, LIMIT, and HAVING clauses.

Example Syntax

SELECT col1, AggregateFunction(col3)

FROM table;

GROUP BY col1, col2, … coln

ORDER BY col2;

Connect to the terminal below by clicking in the widget. Once connected, the command line prompt will show up. Enter or copy and paste the command ./DataJek/Lessons/23lesson.sh and wait for the MySQL prompt to start-up.