When answering a question please: Read the question carefully. Understand that English isn't everyone's first language so be lenient of bad spelling and grammar. If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem.
Insults are not welcome. Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question. Let's work to help developers, not make them feel stupid. Related Questions. Trigger SQL server that updates all records in a table. Sql error when updating record. How to update record in table.
Insert and update in sql table using datagrid in WPF. How to identify record is not updated in SQL server. Update Record in Sql Table. Pivoting records in SQL. Sql query to fetch latest record. Layout: fixed fluid. Web02 2.
Strip HTML. Encode HTML. Paste as-is. Code block. Quoted Text. The ExecuteScalar method in step 2 returns this value. Since the return type of ExecuteScalar is type object, we use a cast operator to convert the value to int. For simplicity, we showed snippets of code in previous sections to demonstrate the applicable techniques. It is also useful to have an entire code listing to see how this code is used in a working program. Listing 1 shows all of the code used in this example, along with a driver in the Main method to produce formatted output.
This is okay because the object itself will be cleaned up when the CLR garbage collector executes. What is important is that we close the connection when we are done using it.
This program opens the connection in a try block and closes it in a finally block in each method. We use it several times in the Main method to show the current status of the Categories table, which changes after each of the insert, update, and delete commands.
Because of this, it is convenient to reuse to show you the effects after each method call. A SqlCommand object allows you to query and send commands to a database. It has methods that are specialized for different commands. If you only need a single aggregate value from a query, the ExecuteScalar is the best choice. I hope you enjoyed this lesson and welcome you to the next one in this series, Lesson Reading Data with the SqlDataReader.
Follow Joe Mayo on Twitter. We may also earn commissions on purchases from other retail websites. Here are the objectives of this lesson: Know what a command object is. Learn how to use the ExecuteReader method to query data. Learn how to use the ExecuteNonQuery method to insert and delete data. Learn how to use the ExecuteScalar method to return a single value. Introduction A SqlCommand object allows you to specify what type of interaction you want to perform with a database.
Premium Not Free Video Tutorials. Videos A-B. Streamlined Syllabus. February 25, at am. September 16, at am. Talha Ayub says:. January 3, at am. Edwin says:. June 7, at pm. Speak Your Mind Tell us what you're thinking Click here to cancel reply. Wordpress Hashcash needs javascript to work, but your browser has javascript disabled. Your comment will be queued in Akismet! NET Languages Data ;. SqlClient ;. OpenConnection ;. InsertRows ;. SelectRows ;. UpdateRows ;. DeleteRows ;. Close ;. WriteLine "Connection Closed" ;.
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