Mysqlcommand update

After the MySqlCommand object is created, you can call one of the previous methods on it to carry out a database operation, such as perform a query. The results are usually returned into a MySqlDataReader object, and then processed. For example, the results might be displayed as the following code example demonstrates.

When a connection has been created and opened, the code then creates a MySqlCommand object. When the results have been obtained in a MySqlReader object, the results can be processed. In this case, the information is printed out by a while loop. Finally, the MySqlReader object is disposed of by invoking the Close method. The next example shows how to use the ExecuteNonQuery method.

The procedure for performing an ExecuteNonQuery method call is simpler, as there is no need to create an object to store results. This is because ExecuteNonQuery is only used for inserting, updating and deleting data. The following example illustrates a simple update to the Country table:. You can access your MySQL database with mysql and verify that the update was carried out correctly. Finally, you can use the ExecuteScalar method to return a single value. Again, this is straightforward, as a MySqlDataReader object is not required to store results, a variable is used instead.

The following code illustrates how to use the ExecuteScalar method:. This example uses a simple query to count the rows in the Country table. Handling Connection Errors. Using GetSchema on a Connection. Using MySqlCommand. Sometimes, you may want to update just one row; However, you may forget the WHERE clause and accidentally update all rows of the table. See the following employees table from the sample database.

In this example, we will update the email of Mary Patterson to the new email mary. Second, update the email address of Mary to the new email mary. To update values in the multiple columns, you need to specify the assignments in the SET clause.

AddWithValue " loc", location ; cmd. AddWithValue " cat", category ; cmd. AddWithValue " numquery", Convert. Steve Steve k 21 21 gold badges silver badges bronze badges. It's really my first time using this, I plan to clean it up. But for the moment we need it done quick and dirty.

I agree on the dirty part though :- — Steve. Linga Linga 9, 9 9 gold badges 47 47 silver badges 94 94 bronze badges. C Sharper C Sharper 7, 20 20 gold badges 81 81 silver badges bronze badges. Try removing the ' single quotes around the integers?

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