The difference between distinct and group by in MySQL

Simply put, distinct is used to remove duplicates, while group by is designed to aggregate statistics. The two have some similarities in the functions they can achieve, but they should be carefully distinguished.

The simple deduplication operation using DISTINCT is faster than GROUP BY.

distinct supports single-column and multi-column deduplication.
The single-column deduplication method is simple and easy to understand, that is, only one identical value is retained.
Multiple columns are deduplicated based on the specified deduplicated column information, that is, only when all the specified column information is the same will it be considered as duplicate information.

The frequency of group by is relatively high, but just like its function, its purpose is to perform aggregate statistics. Although it is also possible to achieve the function of deduplication, this is not its strong point.

the difference:

1) distinct simply removes duplicate rows from the result;

Group by means grouping by specified columns, and generally aggregate functions are used in select at this time.

2) distinct is to display different records.

Group by means to sort the records by category before querying.

GROUP BY must include an aggregate function in the query results, while DISTINCT does not.

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