Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. Thank you. Microsoft makes no warranties, express or implied, with respect to the information provided here. The DataSet used to update the data source. The number of rows successfully updated from the DataSet. The update is performed on a by-row basis.
For every inserted, modified, and deleted row, the Update method determines the type of change that has been performed on it Insert, Update or Delete. Depending on the type of change, the Insert , Update, or Delete command template executes to propagate the modified row to the data source.
It should be noted that these statements are not performed as a batch process; each row is updated individually. NET Framework data provider. This generation logic requires key column information to be present in the DataSet. For more information see Generating Commands with CommandBuilders.
The Update method retrieves rows from the table listed in the first mapping before performing an update. The event handler receives the SqlRowUpdatingEventArgs argument containing information about the event.
Table lists the properties of SqlRowUpdatingEventArgs used to access information specific to the event. Gets the type of SQL statement to execute to update the row. This is one of the following values: Select , Insert , Update , or Delete.
Gets the UpdateStatus of the Command. This is one of the UpdateStatus enumeration values described in Table The UpdateStatus is set to ErrorsOccurred when an error occurs while updating a row; otherwise it is set to Continue. UpdateStatus can be used to specify what to do with the current and remaining rows during an update. Table describes the UpdateStatus enumeration values.
To batch the update commands generated by the DataAdapter , the solution does the following in the RowUpdating event handler for each row updated:. Once all of the rows have been processed, execute the assembled batch command text against the data source using the ExecuteScalar method of a Command object. The solution delimits the string values for the CategoryName and Description fields in the Categories table from the Northwind database used in this example.
Ensure that strings, dates, and any other fields are properly delimited when values are substituted for parameter names in the DataAdapter. RowUpdating event handler. The attempt to update is made, so the event fires. The following example shows how to use both the RowUpdating and RowUpdated events. The RowUpdating event returns this output:. The RowUpdated event returns this output:. When using Update , there are two events that occur per data row updated. The order of execution is as follows:.
The values in the DataRow are moved to the parameter values. If they has Added rowstate - then dataadapter will try to insert appropriate records. I just checked RowState property and yes it has 'Added' value.
What should I do now? Make it null? Have you checked here: msdn. Oh its a readOnly property. So how could I stop it from inserting 'Added'? Add a comment. Active Oldest Votes. Andy Korneyev Andy Korneyev I have a database table that I am trying to get to update based on if the user changes the Description on an item. I have all the adapters and commandbuilders set up as well as a. However, the database item description never updates. Update inserts fine but never updates the table in question.
ARidder it is almost impossible to help you without having a look into your actual code. Create a new question, provide your code sample - and somebody surely will help you with your problem. I had created a question not long after I wrote this comment and after doing a little debug mode code tracing i figured out what i was doing wrong and posted the answer on my question.
I was using a new DataTable that had a previous value in the row of null so it was ignored by the DataAdapter since no line had a null value in the database. I modded the code and got it running proper. Just to add to the end of the selected answer, we can also set RowState to Modified by calling dataTable. AcceptChanges ; dataTable.
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