ADO.NET connection string

[apostolos]

hi, I am using the ADO.NET provider and this is the connection string that i am using to connect to the server.

"provider=AttunityConnect;BindURL=username:passwor d@host/workspace;database=mydatabase;Binding=my_bind;"

Unfortunately i am getting an error while i try to connect. This is the error i am getting:

An invalid connection string argument has been supplied or a required connection string argument has not been supplied.
Source : Attunity.AisClient

Void Validate()
Stack Trace : at Attunity.Data.AisClient.ConnectionString.Validate( )
at Attunity.Data.AisClient.AisConnection.set_Connecti onString(String value)
at Attunity.Data.AisClient.AisConnection..ctor(String connectionString)


Is the connection string i am using correct?
Do I need any extra parameters in the connection string??
any help??

thanks a lot,
Apostolos

[JeffS]

Apostolos,

The BindURL and Binding attributes are incompatible in a connection string. The former is to directly access the Attunity daemon on a remote machine. The latter is to access a non-default binding on the local machine. Note that in the BindURL attribute the binding on the remote machine is implied by the workspace argument since a workspace has only one binding associated with it. Also by using the database attribute you are limiting the connection so that it can access objects only in mydatabase and not in any other data sources (in the binding associated with workspace if you use BindURL or in the my_bind binding if you use Binding).

Regards,
Jeff

[apostolos]

Jeff,

thanks for the help. So what you are saying is that, I don’t need to include the Binding attribute? I also tried the following connection string:
"provider=AttunityConnect;BindURL=username:passwor d@host/workspace;database=mydatabase"
but I am still getting the same error.

I was using the same connection string with a different provider and there were not any errors. I was using OleDb, and now I am trying to use the ADO.NET provider.

Can I have a sample of a connection string with the proper attributes that I have to use?

thanks again,
Apostolos

[JeffS]

Apostolos,

Did you see the "ADO.NET sample" thread in the ADO.NET Provider forum, http://www.attunity.com/forums/ado-net-provider/ado-net-sample-455.html? The connection string format does not use the BindURL syntax. The relevant line of code is simply:

ConStr = "server=alpha;Port=4820;Database=rdb"

The sample does not contain all the attributes you using. I am investigating what they are. In the meantime you can either try it with only those 3 (if you can use the default workspace and anonymous login) or try user, password, and workspace for the missing attribute names, i.e., taking what you have in your BindURL

ConStr = "server=host;port=2551;database=mydatabase;user=us ername;password=password;workspace=workspace"

If the user attribute does not work you could try username or userid.

Regards,
Jeff

[DrorHarari]

The 'provider=AttunityConnect' syntax belongs with the COM based ADO provider, not the ADO.NET provider.

The connect string is the documented in the help file contained in the Attunity ADO.NET kit. I have attached an excerpt to this post.

Attachment 66

[apostolos]

Dear Jeff,
thanks a lot for your help. I used the connection string that you sent me and it works fine… The connection string that I posted was the one I was using with an old version of attunity provider (oledb) which it was working. Since I am facing many problems now with my .net applications I thought to start using the Attunity.AisClient and see the difference. I took a look on the ADO.NET sample. Are there any more examples? Using stored procedures and datareaders? Because I have some problems executing datareaders with stored procedures.

For example why this code gives me an error:
Error Message "Object reference not set to an instance of an object.”


Dim conn As New Attunity.Data.AisClient.AisConnection(conString)
Dim AisCommand As New Attunity.Data.AisClient.AisCommand
Dim AisReader As Attunity.Data.AisClient.AisDataReader

conn.Open()
AisCommand = conn.CreateCommand
AisCommand.CommandType = CommandType.StoredProcedure
AisCommand.CommandText = "vebill:up_MyStoredProcedure"

AisReader = AisCommand.ExecuteReader(CommandBehavior.Sequentia lAccess)

Label.Text = Convert.ToString(AisReader.Item(0))


But this code does not?

Dim conn As New Attunity.Data.AisClient.AisConnection(conString)
Dim AisCommand As New Attunity.Data.AisClient.AisCommand
Dim AisReader As Attunity.Data.AisClient.AisDataReader

conn.Open()
AisCommand = conn.CreateCommand
AisCommand.CommandType = CommandType.StoredProcedure
AisCommand.CommandText = "vebill:up_MyStoredProcedure"

AisReader = AisCommand.ExecuteReader(CommandBehavior.Sequentia lAccess)


If AisReader.Read Then
Label.Text = Convert.ToString(AisReader.Item(0))
End If



thanks again for your help,
Apostolos

[Adeeb Mass'ad]

Since this thread is quiet for a while, we wanted to check if the problem was resolved?

Also, I wanted to note that when a DataReader object is returned, you have to call the Read method at least once to initiate getting the data.

You can also create a loop reading all the returned rows, for example:

While AisReader.Read()
ListBox1.Items.Add(Convert.ToString(AisReader.Item (0)))
End While

[apostolos]

Hi,

the problem with the connection string was solved.

About the AisReader, in order to read any data from the AisReader you should first call the AisReader.Read method, otherwise it gives an error.

thanks
Apostolos

[Adeeb Mass'ad]

Hi,

In classic ADO you will get the first record after executing a query. In ADO .NET the the default position of the DataReader is just before the first record. Therefore, you must call Read to start accessing any data.

Also note, that the Read method repositions the DataReader to the next row, thus you can keep looping until the last record is returned.