MySQL query Solution

MySQL query solution: Mysql calculates the values of multiple fields. The original database is as follows. All fields are of the int type.

+----+---------+---------+| id | column1 | column2 |+----+---------+---------+|  1 |       1 |       2 ||  2 |       3 |       4 ||  3 |       5 |       6 |+----+---------+---------+

 

The expected output result value is

column1 * column2+----+--------+| id | Result |+----+--------+|  1 |      2 ||  2 |     12 ||  3 |     30 |+----+--------+

 

The SQL statement used is

SELECT id, (column1 * column2) AS Result FROM table;

 

Note: Mysql supports all commonly used Arithmetic Operators +,-, *,/, %, DIV (Division),-(negative) the column1 * column2 expression cannot be written as 'column1 '* 'column2' or 'column1 * column2 '. Mysql uses multiple field values as text links or databases, this time, you want to output column1 * column2 in the string format, that is:

+----+--------+| id | Result |+----+--------+|  1 | 1 * 2  ||  2 | 3 * 4  ||  3 | 5 * 6  |+----+--------+

 

Use the following SQL statement

SELECT id, CONCAT(column1, ' * ', column2) AS Result  FROM table;

 

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