SqlDataApapter Parameters Question

  • Thread starter Thread starter Philip Tepedino
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Philip Tepedino

Hello,

I'm having a hard time getting used to all this new ADO stuff.
I have many applications written in VB6 and am starting to slowly re-do them
in .NET
What I've read suggests that I should use parameters to pass information to
a query string instead of creating the string piece by piece. Thats fine
with me, I like that. My problem is: Whats the best way to deal with
parameters that you don't have info for?

Here is an example:
I set a SqlCommand to something like "SELECT * FROM tblEmps WHERE (ID = @ID)
AND (Unit LIKE @Unit)

So lets say my form has two text boxes, txtID and txtUnit
Unit is a string, and ID is an integer

Now the user fills in the txtUnit textbox with "John" or something, and
leaves the ID (txtID) blank.

If I add both parameters to the adapter, then nothing shows up because it is
adding "" (or a 0 when converted to integer i guess) to the @ID parameter.
IF I don't add a value for @ID, then it gives me an exception error.

My question is:
Is there a way I can NOT add a parameter that was defined in my SqlCommand?
and if not, how do I deal with textboxes that the user might not fill out
(its easy for strings.. just use LIKE and add "%" as the parameter)

Am I doing this the wrong way? How should I deal with forms that have many
inputs, some of which might be left blank?

Thanks for any help,

Philip Tepedino
Siemens Westinghouse Generation Services
Software/Database Development
(e-mail address removed)
 
For this case, one approach would be to pass a "%" as the LIKE argument
parameter--it's perfectly alright--but the LIKE expression is intended for
strings--not integers. Use BETWEEN or other numeric expressions for numbers.
If you create a stored procedure to run this query you can specify default
parameter values as well.

hth

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www.betav.com
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