Usage of in in mysql

IN operator is used to check whether a value is contained in a list of values. The syntax is: SELECT * FROM table_name WHERE column_name IN (value1, value2, ..., valueN); The IN operator can be used with value lists, variables or subqueries, and supports multiple value type comparisons. It is more efficient than the OR operator, especially when the list contains multiple values.

Usage of IN in MySQL

Question: IN# What is the role of ## operator in MySQL?

Answer: IN operator is used to check whether a value is contained in a list of values. The syntax is:

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

Detailed explanation:

##IN

The operator compares a value to a list of values. The expression is true if the value matches any value in the list. Otherwise, the expression is false.

Example:

Get students with grades A, B or C:

<code>SELECT * FROM students WHERE grade IN ('A', 'B', 'C');</code>

IN

Operator supports subquery : <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">&lt;code&gt;SELECT * FROM students WHERE grade IN (SELECT grade FROM grades WHERE score &gt; 80);&lt;/code&gt;</pre><div class="contentsignin">Copy after login</div></div>

Note:

IN
• The values ​​in the list can be constants, variables, or subqueries. The value list can contain any number of values, separated by commas. The
• IN
• operator is generally more efficient than the OR operator, especially when the list contains multiple values. If the
IN
• list is empty, the expression is always false.

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