Question

I have a Select Statement Like this..

Select * From A Join B on A.ID = B.ID
 And A.Gener = 'M'
 And A.Age = 21
 And B.School = 'Bluh'   
--- many more AND Clauses

now these “AND” Clauses are dynamic, they will be build based upon user selection within my vb.net web application….

for example…

if gener.text <> "" Then
   qry = qry & " And A.Gender='M'"

I dont really want to build my SQL query on the fly like this. is there a way of doing it better using LINQ or something else?

my actual SQL Query will contain up to 30 dynamic AND’s (Based upon user selection).

please advise.

Thanks

Answer 1

i would change it this way

Select * From A Join B on A.ID = B.ID
 And (A.Gener = @arg1 or @arg1 is null)
 And (A.Age = @arg2 or @arg2 is null)
 And (B.School = @arg3 or @arg3 is null)

— many more AND Clausesju

this way if you pass null values into procedure they would be logicly ignored – dont know if it works in your case

definetly building dynamic tsql query application side is a invitation for sql injection