How Can I Group Data by Multiple Columns in MySQL?
Can I Group Data by Multiple Columns in MySQL?
MySQL allows you to group data by multiple columns using the GROUP BY clause. This is useful when you want to summarize data based on different combinations of column values.
For example, to group records by the tier_id and form_template_id columns, you can use the following GROUP BY clause:
GROUP BY fV.tier_id, f.form_template_id
This query will return a set of rows, each of which contains the count of records with the same tier_id and form_template_id values. You can then use the results of the query to further analyze your data.
Syntax
The general syntax for the GROUP BY clause is as follows:
GROUP BY col1, col2, col3, ...
You can specify multiple columns in the GROUP BY clause, separated by commas. The columns specified in the GROUP BY clause must be present in the SELECT list of the query.
Example
The following query groups records by the department and job columns and returns the total salary for each combination:
SELECT department, job, SUM(salary) AS total_salary FROM employees GROUP BY department, job;
The results of the query will be a set of rows, each of which contains the department name, job title, and total salary for employees in that department and job.
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