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
expression2are The expression or value to compare.
Usage Example
The following is an example query using the != operator:<code>SELECT * FROM customers WHERE age != 30;</code>This query will return all those whose age is not 30 Customer records.
Comparison with other comparison operators
!= operator is similar to the following 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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