I have two tables, I will call them first-half and second-half (of the year)

Table: first
id   jan  feb  mar  apr
2     80   90  70    60
3     50   40  60    30

Table: second
id   jan  feb  mar  apr
2     50   70  60    90
3     80   60  50    40

I want to do a SELECT that will bring a total of each individual values (jan, feb, mar, apr) from these tables. Fetch by id. I want something like this:

Table: total
id   jan  feb  mar  apr
2    130  160  130   150

How can I make this possible?
ALSO, I will be so thankful if, in that SELECT statement, I can specify the columns I want as comma separated values, that is, I will not always have to pull values of all columns (jan,feb,mar,apr) but I will choose which values I want (say jan,mar,apr) and this is specified as a result of another SELECT statement which will bring required columns, separated by commas (like: jan,mar,apr)

The goal then, is to generate a report (from VB.NET) that shows all this information from table first, second and total
Thank you.

You can use the following SQL Statement

Select A.id, 
(A.jan + B.jan) As JANUARY,
(A.feb + B.feb) As FEBRUARY,
(A.mar + B.mar) As MARCH,
(A.apr + B.apr) As APRIL
 From first A 
Inner Join second B
On A.id=B.id Order By A.id
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