INSERT statement affects 1 row, but the VS Server

问题:

I've checked other Stack Overflow questions to find answers, but I just can't find a solution to this. I am trying to insert string data into a SQL CE (local database).

I can read from the database, but I cannot insert data, regardless of whether I hard-code it or try to add it with parameters.

The table to be modified is called users. It has 3 columns: ID, name, email.

Here is the code I am using:

string connection = Properties.Settings.Default.LocalDBConnectionString;

using (var con = new SqlCeConnection(connection))
{
    con.Open();

    // (I also tried adding with parameters but couldn't get it working.)
    using (var com = new SqlCeCommand("INSERT INTO users (name, email) " +
                                      "VALUES (N'jimmy', N'[e-mail]')", con))
    {
        int numRowsAffected = com.ExecuteNonQuery();

        // This returns '1 row affected' but doesn't actually update the database
        Console.WriteLine(numRowsAffected);
        Console.ReadKey();
    }
}

Although the Console outputs 1, because 1 row is affected, when I go back into the database and check, it has not inserted the new data.

I was following this tutorial, but only the Read works, the Insert or write doesn't work.

I also found this similar Stack Overflow question, but using parameters, still couldn't get it to work.

---

Edit:

My connection string is:

Data Source=|DataDirectory|\LocalDB.sdf

I don't know how to find the Build Settings, it is a Local Database I created within the console application solution, It is stored in the project directory.

I am in "Debug" configuration if that helps?

---

Here is another example I found on the internet:

SqlCeConnection con = new SqlCeConnection(Properties.Settings.Default.LocalDBConnectionString);
con.Open();

SqlCeCommand comInsert = new SqlCeCommand ("INSERT INTO users(name, email) VALUES('value 1', 'value 2')", con);
comInsert.ExecuteNonQuery();

SqlCeCommand comSelect = new SqlCeCommand("SELECT * FROM users", con);
SqlCeDataReader reader = comSelect.ExecuteReader();

while (reader.Read())
{
    Console.WriteLine("{0} {1}", reader["name"], reader["email"]);
    Console.ReadKey();
}

con.Close();

I just copied and pasted this in, and changed the main variables. This example temporarily inserts the data, but when I go to Visual Studio's Server Explorer and view the table, it hasn't updated.

回答1:

Are you sure that the database you INSERT into and the database you're looking at with Server Explorer are the same one?

Remember, we're talking about a file-based DB here (SQL Server CE). So it could be that you're INSERTing into a copy of your DB and then look at the (unchanged) original.

• Is the DB file part of your solution? If so, does it get copied to the output directory (e.g. bin\Debug)? Check the properties of the corresponding solution item, like in the screenshot below (sorry for it being in German):

  

• Where exactly does DataDirectory in the connection string point to? If you're not sure, replace it with something absolute for the time being and see if that solves your problem.

Make double sure that your connection string really points to the database you're looking at with Server Explorer!

回答2:

I guess the problem is here: Data Source=|DataDirectory|\LocalDB.sdf When you run your program from Visual Studio it connects to a database in the Debug (or Release) directory not to that database you have in the project's directory. So, try to use full path instead of Data Source=|DataDirectory|\LocalDB.sdf, try something like this: Data Source=C:\Visual Studio 2008\Projects\MyProject\LocalDB.sdf. It worked for me.

回答3:

I checked my solution explorer connection string and pasted in code file and my problem was solved so make changes to your connection string.