What does in in mysql mean?

The IN operator in MySQL is used to check whether a value is contained in a specified list. The syntax is: SELECT column_name FROM table_name WHERE column_name IN (value1, value2, ..., valueN). Its advantages include high efficiency, ease of use, and scalability. Be aware that it may cause performance issues with large lists or NULL values.

IN operator in MySQL

The IN operator in MySQL is used to check whether a value is contained in in a specified list. The syntax is as follows:

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

How to use the IN operator

You can use the IN operator to compare with multiple values ​​to check whether a specific value exists in the list. For example, to find the "id" column that contains the values ​​5, 7, or 9, you can use the following query:

<code>SELECT id
FROM table_name
WHERE id IN (5, 7, 9);</code>

Benefits of the IN Operator

• Efficiency: For checking whether multiple values ​​are contained in a list, the IN operator is more efficient than using multiple OR operators.
• Easy to use: Using the IN operator is very simple and straightforward, no need to write complex queries.
• Scalability: The IN operator supports any number of values, making it ideal for processing large data sets.

Notes

• The IN operator works well for small lists, but may cause performance issues for large lists.
• The IN operator will always return FALSE if the value being checked is NULL, because NULL is not equal to any value.
• The IN operator is also valid for columns of non-numeric types (such as strings or dates).

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