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:
= > < >= <= <> !=