GREATEST and LEAST
Returns the largest or smallest value from a list of any number of expressions.
Syntax
GREATEST (value [, ...]) LEAST (value [, ...])
Parameters
- expression_list
-
A comma-separated list of expressions, such as column names. The expressions must all be convertible to a common data type. NULL values in the list are ignored. If all of the expressions evaluate to NULL, the result is NULL.
Returns
Returns the data type of the expressions.
Example
The following example returns the highest value alphabetically for
firstname
or lastname
.
select firstname, lastname, greatest(firstname,lastname) from users where userid < 10 order by 3; firstname | lastname | greatest -----------+-----------+----------- Lars | Ratliff | Ratliff Reagan | Hodge | Reagan Colton | Roy | Roy Barry | Roy | Roy Tamekah | Juarez | Tamekah Rafael | Taylor | Taylor Victor | Hernandez | Victor Vladimir | Humphrey | Vladimir Mufutau | Watkins | Watkins (9 rows)