This function is used to return the maximum value.
Syntax
max(col)
Parameters
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