MySQL Create a calculated field

1, Field

Fields are similar to column meanings, database columns are generally called columns, and fields generally refer to calculated fields

2, splicing the field

Stitching--Connecting values together to form a single value

Concat () function

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1 2 3

SELECT Concat (Name, ' (', country, ') as title from the company order by name;

The as title here is the alias, and the title is the computed field.

3. Perform arithmetic calculation

can perform subtraction operations.

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1 2	Select Prod_num*prod_price,prod_name from

4, how to test the calculation

SELECT 3*2, which returns 6

SELECT now (), returns the current time