GREATEST

Purpose

This function returns the maximum value from a list of one or more expressions.

Syntax

GREATEST(expr [, expr ]...)

Parameters

The expr parameter is an expression or a list of expressions. The data type can be NUMBER, FLOAT, BINARY_FLOAT, BINARY_DOUBLE, CHAR, VARCHAR2, NCHAR, NVARCHAR2, or CLOB.

Return type

The database uses the first expr parameter to determine the return type. If the data types of the remaining parameters differ from the data type of the first expr parameter, the database implicitly converts each subsequent parameter to the data type of the first expr parameter.

• If the data type of the first expr parameter is NUMBER, FLOAT, BINARY_FLOAT, or BINARY_DOUBLE, the return type is the same as the data type of the first expr parameter.

• If the data type of the first expr parameter is CHAR, VARCHAR2, or CLOB, the return type is VARCHAR2.

• If the data type of the first expr parameter is NCHAR or NVARCHAR2, the return type is NVARCHAR2.

Examples

• Compare the strings AC, BB, and C and return the largest string.

  obclient> SELECT GREATEST('AC','BB','C') "MAX" FROM DUAL;
  +-----+
  | MAX |
  +-----+
  | C   |
  +-----+
  1 row in set
  

• Compare the integers 1, the string 6, and the value 5.555 and return the largest value.

  obclient> SELECT GREATEST (1,'6','5.555') "MAX" FROM DUAL;
  +-----+
  | MAX |
  +-----+
  |   6 |
  +-----+
  1 row in set