What does != mean in sql?

In SQL queries, the != operator means "not equal to". It compares two expressions. If the results are different, it is true, and if the results are the same, it is false. Syntax: expression1 != expression2. For example: SELECT * FROM customers WHERE age != 30; This query returns all customer records whose age is not equal to 30.

The meaning of != in SQL

In SQL queries, the != operator means "not equal to" . It compares two expressions and returns true if they evaluate differently; otherwise, it returns false.

Operator syntax

<code>expression1 != expression2</code>

where:

• ##expression1 and expression2 are The expression or value to compare.

Usage Example

<code>SELECT * FROM customers WHERE age != 30;</code>

Comparison with other comparison operators

• = (equal to)
• < (less than)
• > (greater than)
• < = (less than or equal to)
• >= (greater than or equal to)

=# Use with the ## (equals) operator to exclude records under certain conditions.

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