SQL IN Keyword
The IN operator is used in a WHERE clause to help filter rows based on whether a column’s value matches any value from a list. It works like a cleaner version of using multiple OR conditions.
SQL IN Syntax
SQL
x
1
SELECT column1, column2, ...
2
FROM table_name
3
WHERE column_name IN (value1, value2, ...);
You can also use it with a subquery:
SQL
1
1
SELECT column1, column2, ...
2
FROM table_name
3
WHERE column_name IN (SELECT column_name FROM other_table);
SQL IN Matching Multiple Values Example
SQL
1
1
SELECT *
2
FROM Patients
3
WHERE gender IN ('M', 'F');

SQL IN Excluding Values Using NOT IN Example
SQL
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1
SELECT *
2
FROM Patients
3
WHERE gender NOT IN ('M');

SQL IN Using A Subquery Example
SQL
1
1
SELECT *
2
FROM Prescriptions
3
WHERE appointment_id IN (
4
SELECT appointment_id
5
FROM Appointments
6
);
