MySQL SQLLesson 6Free preview

MySQL SELECT DISTINCT

This lesson is part of MySQL · All levels

Summary

The SELECT DISTINCT command is used when you want results without duplicate values on selected columns. MySQL compares the value combinations on all the columns mentioned, so one row is considered duplicate only if the entire option column is the same. This feature is useful for finding out unique values such as a list of customer cities or the type of product that has ever been sold.

Key points

DISTINCT removes a row where the entire column of choice is equal to the value
The DISTINCT clause is placed right after SELECT
DISTINCT works on a combination of columns, not per column separately
DISTINCT is different from the primary key which guarantees the uniqueness of stored data

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