MySQL临时表

Question

In the project I'm working I use php language and mysql database.

The reason I thought to use temporary tables was right is because I perform many calculations, and in javascript they would take me a long time.

I must show these tables at screen: .

Table 1:

Total data.         |   6
Average.            |   2984-99
Sum x-Media.        |   5088.9
Sum (x-Media)^2.    |   138092659.8396
Sum (x-Media)^4.    |   1.09E+16
Maximum value.      |   9812.12
Minimum value.      |   18.23

Table 2:

Amount  |   x-Media     |   (x-Media)^2     |   (x-Media)^4
839.12  |   -2145.87    |   704122.3744     |   495788318130.694
18.23   |   18.23       |   332.3329        |   110445.15642241
9812.12 |   11957.99    |   96277698.8944   |   9.27E+15
23.93   |   5.7         |   572.6449        |   327922.18149601
863.21  |   -11094.78   |   745131.5041     |   555220958402.328
6353.33 |   6347.63     |   40364802.0889   |   1.63E+15

All calculations are based on the amount column, this value. I get it from the table tbl_layout_c:

Amount decimal (18,2)
----------
839.12
18.23
9812.12
23.93
863.21
6353.33

So the query is:

1 SELECT amount 
2 (SELECT COUNT(*) FROM tbl_layout_c ) AS total_data
3 (SELECT SUM(amount) FROM tbl_layout_c ) AS total_sum,
4 (SELECT total_sum / total_data AS average,
5 (SELECT amount - average ) AS x_media,
6 (SELECT SUM(x_media)) AS suma_x_media
7 FROM tbl_layout_c

The issue is at LINE 6: (SELECT SUM(x_media)) AS suma_x_media because I get the same value as x_media column . Ex:

Amount      |   x-Media         |   Sum x-Media.
839.12      |   -2145.87        |   -2145.87

And I need:

Amount      |   x-Media         |   Sum x-Media.
839.12      |   -2145.87        |   5088.9

I have trouble when I try to use function sum() in the temporary column (suma_x_media) of the temporary table.. It's not working, I just get the same value as x_media

Anyone have any idea what I'm missing?

Here you can see an example of the Code

Answer 1

try this

select *,sum(x_media) from (SELECT monto, #obtengo el campo monto
(SELECT COUNT(*) FROM tbl_layout_c ) AS total_datos, #contar los registros
(SELECT SUM(monto) FROM tbl_layout_c ) AS suma_total, #suma total
(SELECT MAX(monto) FROM tbl_layout_c ) AS valor_maximo, #valor maximo
(SELECT MIN(monto) FROM tbl_layout_c ) AS valor_minimo, #valor minimo
(SELECT suma_total / total_datos) AS promedio, #promedio
(SELECT monto - promedio) AS x_media #media artimetica
FROM tbl_layout_c)tablealias

I tried in sql Fiddle with your data and It works. your sum(x_media) is 0 with data in sql Fiddle you have if you change the data same as here in TABLE 2 then you can get expected output same mentioned in Table 1.