Updated on 2023-10-25 GMT+08:00

max

This function is used to return the maximum value.

Syntax

max(col)

Parameters

Table 1 Parameter

Parameter

Mandatory

Type

Description

col

Yes

Any type except BOOLEAN

The value can be of any type except BOOLEAN.

Return Values

The return value is of the DOUBLE type.

The return type is the same as the type of col. The return rules are as follows:

  • If the value of col is NULL, the row is not involved in calculation.
  • If the value of col is of the BOOLEAN type, it cannot be used for calculation.

Example Code

  • Calculates the maximum inventory (items) of all offerings. An example command is as follows:
    select max(items) from warehouse;

    The command output is as follows:

    _c0        
    900        
  • When used with group by, it returns the maximum inventory of each warehouse. An example command is as follows:
    select warehourseId, max(items) from warehouse group by warehourseId;

    The command output is as follows:

    warehouseId _c1        
    city1    200        
    city2    300        
    city3    400