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 Update then refreshes the row using the value of the UpdatedRowSource property. Any additional rows returned are ignored.
After any data is loaded back into the DataSet , the OnRowUpdated event is raised, allowing the user to inspect the reconciled DataSet row and any output parameters returned by the command. After a row updates successfully, the changes to that row are accepted.
When using Update , the order of execution is as follows:. The values in the DataRow are moved to the parameter values. The OnRowUpdating event is raised. If the command is set to FirstReturnedRecord , then the first returned result is placed in the DataRow. If there are output parameters, they are placed in the DataRow. The OnRowUpdated event is raised. AcceptChanges is called. When you use the Delete method, the row remains in the DataTable and is marked for deletion.
If you then pass the DataTable or DataSet to a DataAdapter and call Update , the corresponding row in the back end data source is deleted. For more information, see Generating Commands with CommandBuilders. You can control how the values returned from the data source are mapped back to the DataTable following a call to the Update method of a DataAdapter , by using the UpdatedRowSource property of a DbCommand object. By setting the UpdatedRowSource property to one of the UpdateRowSource enumeration values, you can control whether output parameters returned by the DataAdapter commands are ignored or applied to the changed row in the DataSet.
You can also specify whether the first returned row if it exists is applied to the changed row in the DataTable. The following table describes the different values of the UpdateRowSource enumeration and how they affect the behavior of a command used with a DataAdapter. The Update method resolves your changes back to the data source; however other clients may have modified data at the data source since the last time you filled the DataSet.
New rows will be added to the table, and updated information will be incorporated into existing rows. The Fill method determines whether a new row will be added or an existing row will be updated by examining the primary key values of the rows in the DataSet and the rows returned by the SelectCommand. If the Fill method encounters a primary key value for a row in the DataSet that matches a primary key value from a row in the results returned by the SelectCommand , it updates the existing row with the information from the row returned by the SelectCommand and sets the RowState of the existing row to Unchanged.
If a row returned by the SelectCommand has a primary key value that does not match any of the primary key values of the rows in the DataSet , the Fill method adds a new row with a RowState of Unchanged. You must define the PrimaryKey yourself to ensure that duplicate rows are resolved correctly. For more information, see Defining Primary Keys. To handle exceptions that may occur when calling the Update method, you can use the RowUpdated event to respond to row update errors as they occur see Handling DataAdapter Events , or you can set DataAdapter.
ContinueUpdateOnError to true before calling Update , and respond to the error information stored in the RowError property of a particular row when the update is complete see Row Error Information.
No DataRow exists to update. No DataTable exists to update. No DataSet exists to use as a source. The DataTable used to update the data source. The number of rows successfully updated from the DataTable. The DataSet used to update the data source. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Db Data Adapter. Update Method Reference Is this page helpful?
Please rate your experience Yes No. Any additional feedback? Namespace: System. Common Assembly: System. Update DataSet, String. Where do I find these options — lethalMango. If you dragged the DataAdapter onto a form or component, you can right-click it.
If you created the DataAdapter in code, you probably need to change the Select, Insert, Update, Delete commands manually. Look for SqlParameter in your code, and make sure it is using the right type. The DataSet can be changed manually by either opening it in the designer or in an xml editor.
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