find a row in a datatable with a compound key 2

[AccordingToDale]

I have a dataset with several datatables created at runtime. One of
these tables has a compound primary key (2 columns).
The problem I am running into is deleting rows from this datatable. I'm
not sure how to pass the compound key.


What I have been using for datatables with a single column key is this:


objDataset.Tables("dtName").Rows.Find(id).Delete()


Any thots?

Dale

 

[ThatRickGuy]

Not sure if something like this would work:

 dim drs() as datarow = objDataSet.tables("dtName").Select("Field1 = '" & value1 & "' AND Field2 = '" & value2 & "'")
 dim dr as datarow
 for each dr in drs
  dr.delete
 next

-Rick

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I believe in killer coding ninja monkeys.

 

[AccordingToDale]

Perfect. Thanx.

Dale

 

[AccordingToDale]

One more question on this...

I would like to update a particular row in a datatable. (The one with the compound key.)

I would rather not delete the row and insert a new one as I am counting all inserts, updates and deletes in the entire dataset.

So, deleting and inserting would give false information (1 delete and 1 insert) to what is really supposed to take place (1 update).

Obviously there is no datatable.update method, I'm still at a loss b/c I don't know how to find a row with a compound key. Unless there is a better way to update the row?

Can I bother you for one more answer? :>)

Dale

 

[ThatRickGuy]

That gets into an area of ADO.Net I know less of. I run updates via stored procedures and SQL, but a datatable should be able to do an update just like it does a delete or insert.

-Rick

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I believe in killer coding ninja monkeys.

 

[AccordingToDale]

Hey Rick,

I use stored procedures to write to the db, but this app works disconnected from the datasource. It fills a dataset initially, the user can make any changes desired which all happen in the dataset, then click 'Apply' to write everything from the dataset to the db. It's all created and done at run time.

Unfortunately datatables don't have an .update method like .delete or .insertNew. If you can .find a row, then you can set the values directly, which then is considered an update (the row state is set to updated), but I'm stuck at finding the row when using a compound key.

Anyway, thanx for your help.

Dale

 

[ThatRickGuy]

You should be able to use the .Select method to find a row (err, an array of rows) based off anything, that would be an easy way to find the specified row w/ a compound key.

As soon as you update the table the Dataset should attempt to update the database. If the database is unavailable, it will probrably just sit on it.

If you are working on a disconnected system, I would say skip all of the built in update system and use a completely disconnected datatable. When the user hit's apply, cycle through the table and call your stored procedures to do the update/insert/delete.

-Rick

VB.Net Forum forum796 forum855 ASP.NET Forum
I believe in killer coding ninja monkeys.

 

[AccordingToDale]

Essentially you and I are on the same page here, but i'm missing one paragraph... How do you update the row once you find (select) it?

The rest of what you wrote is what I am doing. I cycle through the dataset and for each insert, update and delete I process accordingly via stored procedures.

Dale

 

[SqueakinSweep]

Just amend the datarows(records) as in the following

for each dr in drs
   dr("FieldName1")="Test"
   dr("FieldName2")=12
next

Sweep
...if it works dont f*** with it
...if its f****ed blame someone else
...if its your fault that its f***ed, say and admit nothing.

 

[AccordingToDale]

AARRGGHHH!!! Of course!

I was trying this before but it wasn't working. So, I'll take a little advice from your signature and say and admit nothing. ;>)

Thanx again.

Dale

 

[ThatRickGuy]

LOL, okay. Heh, thanks for filling the page Sweep!

-Rick

VB.Net Forum forum796 forum855 ASP.NET Forum
I believe in killer coding ninja monkeys.