MAX
Function Description
MAX() is a type of aggregate function that calculates the maximum value of a set of values.
Function Syntax
> MAX(expr)
Parameter definition
| Parameters | Description |
|---|---|
| expr | Column name of any numeric type and string column |
Return value
Returns the maximum value in the expr column, and you can also use strings in MAX(), which will return the maximum string value.
Example
> drop table if exists tbl1,tbl2;
> create table tbl1 (col_1a tinyint, col_1b smallint, col_1c int, col_1d bigint, col_1e char(10) not null);
> insert into tbl1 values (0,1,1,7,"a");
> insert into tbl1 values (0,1,2,8,"b");
> insert into tbl1 values (0,1,3,9,"c");
> insert into tbl1 values (0,1,4,10,"D");
> insert into tbl1 values (0,1,5,11,"a");
> insert into tbl1 values (0,1,6,12,"c");
> select max(col_1d) from tbl1;
+-----------------+
| max(col_1d) |
+-----------------+
| 12 |
+-----------------+
> select max(col_1c) as m1 from tbl1 where col_1d<12 group by col_1e;
+------+
| m1 |
+------+
| 5 |
| 2 |
| 3 |
| 4 |
+------+