ORDER BY RANDOM() in SQL

ORDER BY RANDOM() is used to return rows in a random order. It’s useful when you want to shuffle or randomly select rows from a table.

Syntax:

SELECT *FROM table_nameORDER BY RANDOM();

Examples:

Select all rows in random order:

SELECT *FROM employeesORDER BY RANDOM();

Select 5 random rows:

SELECT *FROM employeesORDER BY RANDOM()LIMIT 5;

Notes:

• PostgreSQL and SQLite use RANDOM() for random ordering.

• MySQL uses ORDER BY RAND() instead.

• Using random order can be slow on large tables because it must assign a random value to every row before sorting.

MySQL version:

SELECT *FROM employeesORDER BY RAND()LIMIT 5;

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