How to express inclusion in sql

The IN operator is used in SQL to indicate inclusion, and its syntax is "column_name IN (value1, value2, ...)". Extended representations include NOT IN, ANY, and ALL, which check whether a value is not in a list, exists in a subquery, or exists in all subquery rows.

In SQL, it means containing

In SQL, you can use the IN operator to express Include. IN Operator checks whether a value is contained in the specified list.

Syntax:

<code>SELECT column_name
FROM table_name
WHERE column_name IN (value1, value2, ...)</code>

Example:

Find all employee names that contain specific letters:

<code>SELECT employee_name
FROM employees
WHERE employee_name IN ('John', 'Mary', 'Bob')</code>

Extended representation:

In addition to the basic IN operator, SQL also provides the following extended representation:

• ## NOT IN: Checks whether a value is not contained in the specified list.
• ANY: Checks whether a value is contained in any rows returned by the subquery.
• ALL: Checks whether a value is contained in all rows returned by the subquery.

Example:

Find all orders that do not contain a specific customer:

<code>SELECT order_id
FROM orders
WHERE customer_id NOT IN (12345, 67890)</code>

Find all orders that contain at least one over $100 Customer of the order:

<code>SELECT customer_id
FROM customers
WHERE customer_id IN (SELECT customer_id FROM orders WHERE amount > 100)</code>

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