Compare functions and operator overview

Name	Description
>	greater than
>=	greater than or equal to
<	Less than
<>,!=	Not equal
<=	Less than or equal to
=	equals
BETWEEN … AND …	Between the two values ​​
COALESCE	Returns the first non-null value
IN()	In the collection
IS	Test whether the value is a Boolean value. If it is a Boolean value, it returns “true”
IS NOT	Test whether the value is a Boolean value, negative usage of IS
IS NOT NULL	Not empty
IS NULL	empty
ISNULL	Use instead of = to test whether the value is NULL.
LIKE	Fuzzy Match
ILIKE	Fuzzy matching, same as LIKE. But it is not case sensitive.
NOT BETWEEN … AND …	Not between two values ​​
NOT IN	Abbreviation of multiple XOR conditions
NOT LIKE	N fuzzy matching, negative usage of Like

The results of the comparison operation are TRUE, FALSE or NULL. These operations are valid for both numbers and strings. A string can be automatically converted to a number, and a number can be automatically converted to a string as needed.

The following comparison operators can be used not only to compare scalar operations, but also to compare line operations:

= > < >= <= <> !=