The meaning of in in sql

IN operator checks whether a value is included in the specified value list. The syntax is: SELECT * FROM table_name WHERE column_name IN (value1, value2, ..., valueN). It has the advantage of improving query performance, especially when you need to check whether a value is contained in a large number of values. Additionally, the IN operator can be used with a subquery or NOT operator.

The meaning of IN operator in SQL

IN operator is used to check a certain value in SQL Whether included in a specified set of values. It uses the following syntax:

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

where:

• table_name is the table from which data is to be retrieved.
• column_name is the column whose value is to be checked.
• value1, value2, ..., valueN is the list of values ​​to check.

How to use the IN operator

To use the IN operator, just put the value you want to check within parentheses. For example, to find out which customers in table customers live in New York or California, you could write the following query:

<code>SELECT * FROM customers WHERE state IN ('NY', 'CA');</code>

Advantages of the IN Operator

The main advantage of using the IN operator is that it can improve query performance. When you need to check whether a value is contained in a large number of values, using the IN operator is more efficient than using multiple OR conditions.

Other related information

• The IN operator can also be used with a subquery to check whether a value is contained in the value returned from another query. The results are focused.
• The IN operator can also be used with the NOT operator to check if a value is not contained in a specified list of values.

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