sql = and <> follow the sql-92 standard settings set ANSI_NULLS on

Description

The SQL-92 standard requires that the value be FALSE when the null value equals (=) or does not equal (<>) is compared.
    
    When SET Ansi_nulls is OFF, the Equals (=) and not Equals (<>) comparison operators do not comply with the SQL-92 standard.
Use the WHERE COLUMN_NAME = null SELECT statement to return rows that contain null values in column_name. Use the WHERE column_name <> NULL SELECT statement to return rows that contain non-null values in the column. Also, use the SELECT statement in WHERE column_name <> xyz_value to return all rows that are not xyz_value and not null.

sql = and <> follow the sql-92 standard settings set ANSI_NULLS on