The difference in usage of and and or in mysql

The AND operator in MySQL requires all conditions to be true, while the OR operator requires at least one condition to be true. AND has a higher priority than OR, and the AND operation is performed first.

The difference between AND and OR operators in MySQL

Overview

AND and OR are commonly used logical operators in MySQL, used to combine multiple conditions for query. They differ in how they handle true and false values.

AND Operator

• The result of the AND operation is true if all conditions are true.
• If either condition is false, the result of the AND operation is false.

OR operator

• If any one condition is true, the result of the OR operation is true.
• The result of the OR operation will be false only when all conditions are false.

Example

Assume the following conditions:

• age > 18
• gender = 'M '

AND operation (age > 18 AND gender = 'M')

• age > 18 is true, gender = 'M' ' is true
• The result is true according to the AND rule

This will return only rows that meet these two conditions.

OR operation (age > 18 OR gender = 'M')

• age > 18 is true
• According to the OR rule , the result is true

This will return rows that meet any of these conditions, including only rows that meet age > 18 or gender = 'M'.

Priority

The AND operator has higher precedence than the OR operator. If an operation contains both AND and OR, the AND operator will be executed first.

Usage Guide

• AND: is used to find rows that meet multiple conditions at the same time.
• OR: is used to find rows that meet at least one condition.
• Priority: Consider the precedence of the AND operator to ensure the correct order of operations.

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