将结果查询为所需格式（MySQL）

Question

Hello everyone i have some question about query on MySQL database.

I have table name TEST like this

DATE        PRODUCT
2008-01-01  10
2008-01-01  20
2008-02-01  30
2008-02-01  40

And i want a query that can select like this

DATE        PRODUCT
2008-01-01  15
2008-02-01  35

Where PRODUCT is came from AVERAGE value from their DATE. Thanks

Answer 1

You could group the results by the date and apply the avg aggregate function:

SELECT   `date`, AVG(`product`) AS 'Product'
FROM     `test`
GROUP BY `date`

Answer 2

试试这个查询：

select date, AVG(PRODUCT) from TEST GROUP BY date