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c#t-sqlsqlcommandparameterized-query

SqlCommand.Parameters.AddWithValue Not Returning Correct Results


I'll admit that I'm a bit of a newbie (though learning fast!) when it comes to using parameterized queries in C#, so I'm probably just overlooking something here, but I can't seem to figure out how to get a parameterized query to work for me.

Here is a much simplified example. If more information is needed, I am certainly willing to supply it.

using (SqlCommand command = connection.CreateCommand())
{
    command.CommandText = "SELECT COUNT (*) FROM Sites WHERE ((STATE LIKE '@STATE'));
    command.Parameters.AddWithValue("@State", "MA");

    connection.Open();
    SqlDataReader reader = command.ExecuteReader();
    while (reader.Read())
    {
        count = Convert.ToInt32(reader[0]);
    }
    reader.Close();
    connection.Close();
}

Using SQL Server Profiler, I can see that the following query is being issued:

exec sp_executesql N'SELECT COUNT (*) FROM Sites WHERE ((STATE LIKE ''@STATE''))',N'@STATE nvarchar(2)',@STATE=N'MA'

If I run that query directly in SQL Server Management Studio, it returns 0. If, however, I modify the query like this:

exec sp_executesql N'SELECT COUNT (*) FROM Sites WHERE ((STATE LIKE ''MA''))',N'@STATE nvarchar(2)',@STATE=N'MA'

And run it, I get a count of 51 back, which is correct.

What am I missing here?


Solution

  • you don't need quotes around @STATE