MySQL Group By

Group By clause is used to group the result set by one or more column.

Suppose we have students table as follows -

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When we count number of students, we will get this output -

SELECT COUNT(*) FROM students;
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But what if we want to get the students count based on their age. For this we are using GROUP BY clause. The statement is as follows -

SELECT age, count(*) FROM students GROUP BY age;
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