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How to use in in sql

Apr 29, 2024 pm 02:00 PM

The IN operator in SQL is used to check whether a value is included in a specified set of values. Its syntax is: SELECT column_name FROM table_name WHERE column_name IN (value1, value2, ..., valueN). It can be used to check a single value (e.g. SELECT customer_name FROM customers WHERE customer_id IN (10)) or multiple values ​​(e.g. SELECT customer_name FROM customers WHERE c

How to use in in sql

IN operator in SQL

##Function: IN operator is used to check whether a value is included in a specified set of values ​​
##.

#Syntax:

SELECT column_name
FROM table_name
WHERE column_name IN (value1, value2, ..., valueN);
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Parameters:

##column_name:
    The column name of the value to be checked
  • value1, value2, ..., valueN:
  • List of values ​​to check, can be constants, subqueries, or values ​​selected from other tables
  • How to use:

Use the IN operator to enclose a set of values ​​in parentheses

    Place the IN operator in the WHERE clause. And followed by the column name to be checked
  1. List the value to be checked after the IN operator
  2. ##Example:
SELECT customer_name
FROM customers
WHERE customer_id IN (10, 15, 20);
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This query will return the names of all customers with a customer ID of 10, 15 or 20

Note:

##The IN operator can check for nulls. value, but it will return NULL. The performance of the IN operator is affected by the length of the value list. For longer lists, you can use the EXISTS or NOT IN operator to improve performance.

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