The difference between any and some in sql

ANY and SOME are both predicates in SQL used to match subquery and main query rows. The difference is: ANY: checks whether the subquery has matching rows, regardless of the number of rows returned. SOME: Checks whether the subquery has at least one matching row, but does not care about the number of rows returned.

The difference between ANY and SOME in SQL

In SQL queries, ANY and SOME are both used for matching A predicate that compares any or some of the rows returned by the subquery with the rows returned by the main query. But they have subtle differences in usage and semantics.

Usage

• ANY: In the comparison of subqueries, if any row returned by the subquery matches the value of the main query row , then ANY returns true.
• SOME: In a comparison of subqueries, SOME returns true if some (but not necessarily all) of the rows returned by the subquery match the values ​​of the main query rows.

Semantics

• ANY: represents an existence check, that is, as long as the subquery returns at least one matching row, ANY The condition is true no matter how many rows are returned.
• SOME: represents a quantity check, that is, the subquery must return at least one matching row, otherwise the SOME condition is false. If multiple rows are returned, SOME does not take their number into account.

Example

ANY

<code class="sql">SELECT * FROM employees
WHERE salary > ANY (SELECT salary FROM managers);</code>

This query returns employee records with a salary greater than any manager. The ANY condition is satisfied if at least one manager's salary is greater than the employee's salary.

SOME

<code class="sql">SELECT * FROM customers
WHERE city = SOME (SELECT city FROM orders);</code>

This query returns records of customers who live in at least one of the cities specified in the order. The SOME condition is met if at least one order's city in the orders table matches the customer's city.

Summary

• ANY checks whether there are matching rows in the subquery, regardless of the number of rows returned.
• SOME checks whether there is at least one matching row in the subquery, but does not care about the number of rows returned.

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