import text files into a database table and calculate one field based on other fields

I hope these questions are sample.
I have two files(either text or csv format).
file1 has two fields A1(date) and B1(double)
file2 has five fields A(date), B(double), C(double), D(double) and E(double).
both files have many cows

Q1: How can import these two files into a table in a database using C# in ASP(a web page)?
Q2: the table of the database has a field F in which the value is based on the calculation of fields of C, D and E in file2) and only negative value in the field E will be involved in the calculation (if it is positive, then the value will be set to zero factor in the equation of the calculation to get value for field F).
the equation is like:
F = (C * constant)/(D + abs(E)) --- if E<0
F =  (C * constant)/(D + 0) --- if E>=0
Thank you very much for the help. 

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