Comparison functions
This topic describes the comparison functions that are supported by PolarDB-X.
The following table describes the comparison functions that are supported by PolarDB-X.
| Function | Description |
|---|---|
| COALESCE() | Returns the first non-NULL expression. |
| GREATEST() | Returns the largest value in a list. |
| IN() | Tests whether a specified value or field is included in a list. |
| ISNULL() | Tests whether an expression is NULL. |
| LEAST() | Returns the smallest value in a list. |
| STRCMP() | Compares the s1 string and the s2 string based on ASCII values. If the ASCII values of the strings are the same, the value 0 is returned. If the ASCII value of the s1 string is larger than that of the s2 string, the value 1 is returned. If the ASCII value of the s1 string is smaller than that of the s2 string, the value -1 is returned. |