I am trying to update and save a row of a database table. I have used a version of this code to just populate a GridView and it works, so I am assuming it has something to do with my SQL statment; I do not get an error, the table just does not update. On the page load event I have the textboxes being populated by the information of the row, and I have a global variable, named 'temp', that will save the title of the row so I can use it in the button's click event.
The error I am getting states that I have not given a value for one of my required parameters. My Locals tab on the debugger shows that every variable has a value, though the one I try to update is not the new data but still the old data. I have looked at several examples and I cannot find the problem though. Thank you for any assistance. This is the details of the Error message.
I changed you commandText as seen below and created a blank database with a table named just like yours and the update worked. I had a record in my database with the title of Wario World, and running the update changed the title to Super Mario Bros. Check if you temp variable is different from your title variable. Also check that you have the record int the table for your temp variable title. The problem, I found out, does not even have to do with the button's click event, it had to do with the page load event.
Since on page load the row's information is loaded and populated into the textboxes, when the button is clicked to update the fields, the page load event triggers again and reloads the old information into fields, essentially saving the old information instead of the new. Therefore the code does not get saved when the button is pressed. Hopefully this helps other people stuck on a similar problem! Using dates in a where clause is always ify as they are floating point numbers and may not match equally.
I'd try and round them or convert them to strings before comparison, e. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Updating row in database using vb. Asked 4 years, 11 months ago. Active 4 years, 11 months ago. 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.
If the field values that identify the row as unique have been modified, after calling AcceptChanges the Original values will no longer match the values in the data source.
AcceptChanges is called automatically for each row during a call to the Update method of a DataAdapter. You can preserve the original values during a call to the Update method by first setting the AcceptChangesDuringUpdate property of the DataAdapter to false, or by creating an event handler for the RowUpdated event and setting the Status to SkipCurrentRow.
The following examples demonstrate how to perform updates to modified rows by explicitly setting the UpdateCommand of a DataAdapter and calling its Update method. This is important, because the Current value may have been modified and may not match the value in the data source.
The Original value is the value that was used to populate the DataTable from the data source. If the tables from your data source have auto-incrementing columns, you can fill the columns in your DataSet either by returning the auto-increment value as an output parameter of a stored procedure and mapping that to a column in a table, by returning the auto-increment value in the first row of a result set returned by a stored procedure or SQL statement, or by using the RowUpdated event of the DataAdapter to execute an additional SELECT statement.
For more information and an example, see Retrieving Identity or Autonumber Values. In many circumstances, the order in which changes made through the DataSet are sent to the data source is important. For example, if a primary key value for an existing row is updated, and a new row has been added with the new primary key value as a foreign key, it is important to process the update before the insert.
You can then pass the returned DataRow array to the Update method of the DataAdapter to process the modified rows. By specifying a subset of rows to be updated, you can control the order in which inserts, updates, and deletes are processed.
For example, the following code ensures that the deleted rows of the table are processed first, then the updated rows, and then the inserted rows. The sample uses DataAdapter.
AcceptChangesDuringFill to clone the data in the database. If the property is set as false, AcceptChanges is not called when filling the table, and the newly added rows are treated as inserted rows. So, the sample uses these rows to insert the new rows into the database. The samples uses DataAdapter. Posted 7-Aug am soeun tony.
Add a Solution. Top Rated Most Recent. Accept Solution Reject Solution. Hi Tony, even if it sounds like a homework, try this. Use Expression property of a column to update it to a desired value. Copy Code. Add your solution here. OK Paste as. Treat my content as plain text, not as HTML. Existing Members Sign in to your account.
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