Question

I want to pass an array of strings as a SQL parameter, but when I execute the command, it throws an exception that says “Object must implement IConvertible”. Here is the code (all three columns are nvarchar):

Public Sub sendsms(messageBodies As String(), ByVal recipientNumbers As String(), Optional ByVal chkMsgIds As string() = Nothing) 
    Dim con As New SqlConnection
    con.ConnectionString = connection.Sms
    Dim cmd As New SqlCommand("insert into sentmessage (text,id,number) values (@text,@id,@number)", con)
    cmd.Parameters.Add("@text", Data.SqlDbType.NVarChar, n).Value = messageBodies 
    cmd.Parameters.Add("@id", Data.SqlDbType.NVarChar, n).Value = chkMsgIds
    cmd.Parameters.Add("@number", Data.SqlDbType.NVarChar, n).Value = recipientNumbers
    con.Open()
    cmd.ExecuteNonQuery()
    con.Close()
    cmd.Dispose()
End Sub

I created this routine to insert huge amounts of records into the database, what is correct approach?

Answer 1

Typically, you would just execute multiple insert commands, one per row, such as:

Public Sub sendsms(messageBodies As String(), ByVal recipientNumbers As String(), Optional ByVal chkMsgIds As string() = Nothing) 
    Using con As New SqlConnection()
        con.ConnectionString = connection.Sms
        con.Open()
        For Each body As String In messageBodies
            Using cmd As New SqlCommand("insert into sentmessage (text,id,number) values (@text,@id,@number)", con)
                cmd.Parameters.Add("@text", Data.SqlDbType.NVarChar, n).Value = body
                cmd.Parameters.Add("@id", Data.SqlDbType.NVarChar, n).Value = chkMsgIds
                cmd.Parameters.Add("@number", Data.SqlDbType.NVarChar, n).Value = recipientNumbers
                cmd.ExecuteNonQuery()
            End Using
        Next
    End Using
End Sub

However, in SQL Server 2008, they added support for a new multi-row insert syntax which is explained here:

http://blog.sqlauthority.com/2008/07/02/sql-server-2008-insert-multiple-records-using-one-insert-statement-use-of-row-constructor/

For instance, you could execute a command such as:

insert into sentmessage (text,id,number) values 
('First',1,1),
('Second',2,2),
('Third',3,3)