query dataset for distinct records

[Guest]

Hey all,
I have an asp.net app.
I'm trying to load a drop-down list from a dataset, but I only want the
unique records of the particular field, is there a way I can do this?

thanks,
rodchar

 

[Imran Koradia]

Your query should look like:

SELECT DISTINCT ColumnName FROM TableName

This will return the unique records for that particular column from your
table.

hope that helps..
Imran.

 

[Guest]

But where would I put that select statement to pull it out of an already
populated database?

 

[Imran Koradia]

oops..sorry. Towards the end of the day in office..you know how that goes

Anyway, there is no direct way of filtering out distinct values from a
datatable in a dataset. Here are a couple of options you have:

1. You could create a new DataColumn and create a unique constraint on it
and then copy the contents from your original data column to this new
column. It'll throw up an error when you try to enter duplicate values. You
can suppress the error so that you don't end up with a chain of exceptions.

2. here's another solution:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;325684


hope that helps..
Imran.

 

[Guest]

thank you for the tips.

oops..sorry. Towards the end of the day in office..you know how that goes

Anyway, there is no direct way of filtering out distinct values from a
datatable in a dataset. Here are a couple of options you have:

1. You could create a new DataColumn and create a unique constraint on it
and then copy the contents from your original data column to this new
column. It'll throw up an error when you try to enter duplicate values. You
can suppress the error so that you don't end up with a chain of exceptions.

2. here's another solution:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;325684


hope that helps..
Imran.

 

[Cor Ligthert]

Rodchar,

In addition to Imran,

When you have an already filled datatable you can use this routine that I
once made to get those values you want.

http://groups.google.com/groups?selm=uE#[email protected]

I hope this helps?

Cor