The syntax for expressing inequality in SQL is "!=". Its usage is: column name != value. Additionally, you can use "<>" instead of "!=", and for NULL values, use IS NULL or IS NOT NULL for comparison. In the WHERE clause, multiple not-equal conditions can be concatenated to form complex queries.
The syntax for expressing not equal in SQL
In SQL, use the "!=" operator to express not equal equal.
Usage:
列名 != 值
For example:
SELECT * FROM table_name WHERE column_name != 'value';
Other notes:
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