无法弄清楚如何编写 MySQL 查询

Question

I am trying to write a MySQL select statement which will use table1 and table2 to generate a table3 .

table1

id	Month	Year	Name	Length	Breath
1	January	2002	Square	5	2
2	February	2003	Circle	6	3
3	March	2004	Cylinder	7	4
4	April	2005	Cube	8	5
5	May	2006	Quadilateral	9	6

table2

id	Month	Year	Name	Frequency	Area	Volume
1	January	2002	Square	1	20	50
2	Febrauy	2003	Circle	2	25	55
3	March	2004	Cylinder	3	Null	60
4	April	2005	Cube	4	35	65
5	May	2006	Quadilateral	5	40	Null

table3 the generated table should be like this.

Name	Type	Month	Year	Length	Breath	Frequency	Volume/Area	Cum_Area	Cum_Volume	Area	Volume
Square	2d	January	2002	5	2	1	2.5	20	50	20	50
Circle	2d	February	2003	6	3	2	2.2	45	105	25	55
Cylinder	3d	March	2004	7	4	3	2	45	165	30	60
Cube	3d	April	2005	8	5	4	1.86	80	230	35	65
Quadilateral	4d	May	2006	9	6	5	1.75	120	230	40	70

In the statements I've tried whenever the cumulative column encounters the first null value, every row from then on is null.

Also, how do I write the type column? I'd like square and circle to be '2d'; cube and cylinder to be '3d' and Quadrilateral to be '4d'.

Table 1 and 2 have the Name, Month and Year column in common.

Answer 1

I don't finish to understand what is your logic or why you don't have ids on the second table. But assuming what you write, this is a SUGGESTION.
Update your question I'll glad to update my answer.

Assuming null means 0:

SELECT
table1.Name,
CASE table1.Name 
WHEN Square THEN '2d'
WHEN Circle THEN '2d'
WHEN Cylinder THEN '3d'
WHEN Cube THEN '3d'
WHEN Quadilateral THEN '4d'
END as Type,
table1.Month,
table1.Year,
table1.Length,
table1.Breath,
table2.Frequency,
(IFNULL(table2.Volume,0) / IFNULL(table2.Area,0)) as 'Volume/Area',
//I don't understand what do you need in this field,
//I don't understand what do you need in this field,
table2.Area,
table2.Volume
FROM table1 
JOIN table2
ON table1.Name = table2.Name AND table1.Month = table2.Month AND table1.Year = table2.Year