The grouping and analysis of database table entries is of practical interest in many applications. Solving this kind of tasks with MySQL tools allows you to perform large amounts of routine work quickly and efficiently.
However, it should be borne in mind: "purity" of the result will depend on many factors. The MySQL group by construct is executed as written by the programmer, but its algorithm may depend on the query execution time and the sampling frequency.
The syntax of a grouping operation in a query
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