Streaming

Have any of you used the ADODB Stream before? I'm trying to put a Memory Stream into a database and am having trouble with the syntax...

Any help or example code you all could provide would be great.

Thanks,

Squirrelly1

What kind of database?

It's an Access Database. I've been using the Microsoft.Jet.OLEDB.4.0 provider...


Thanks,

Squirrelly1

I haven't used Access in a long time. Is there a datatype for storing large binary data? If there is, the memory stream has a ToArray method for converting it into a binary array.

Yes, you can store Long Binary Data in an OLE field in an Access Database...

ToArray you say?

I'll look into it. Thanks,

Squirrelly1

Ok... So I can convert the MemoryStream to a binary array. Now how do I get that binary array into the OLE field...

I have tried many variations of the following, but none have worked so far...

VB Code:

Dim myADOStream As New ADODB.Stream
 
        ConnectToRecordset("SELECT * FROM myTable")
        AddRecord()
        SetVal("Name", Name)
        myADOStream.Open()
        myADOStream.Type = ADODB.StreamTypeEnum.adTypeBinary
        myADOStream.Write(SerializeList(myArrayList).ToArray)
        RS.Fields("Data").Value = myADOStream.Read()
        Update()
        Close()

This code goes through all right, but when I check the database, there is NOTHING in the "Data" field of my recordset :(

It should at least say somethingl like "Long Binay Data" or something like that... right?

Thanks,

squirrelly1

Why are you using ADO and not ADO.NET?

LOL... Probably because I could program ADO with my eyes shut and half asleep (the latter is actually pretty common for me :P)

Do you know of any good resources for programming with ADO.Net? Is it easier?

Thanks,

Squirrelly1

Do you know of any way to do this with ADO.Net?

Sq1

If it was SQL Server, it would be something like:

Dim buffer() As Byte = memStrm.ToArray()

' Construct INSERT Command
Dim sqlCommand as new sqlClient.SqlCommand
Dim strSQl as String

strSQL = "INSERT INTO MyTable (MyData) VALUES (@MyData)"

sqlCommand.Parameters.Add("@MyData", SqlDbType.Image, buffer.Length).Value = buffer

SQLConn.Open()

sqlCommand.ExecuteNonQuery()

SQLConn.Close()

I haven't tried it with Access though. You probably have to use the OleDB stuff instead of the SQL Client stuff, and I think params are ? instead of @. But the code should be something similiar.

what does the @ symbol stand for?

Sq1

In SQLClient, the @ is used to mark a parameter (that then has to be provided in the SQLCommand.Parameters collection). OleDB works a little bit different in that it uses ? instead of the @ParamName. I haven't really played with it so I'd suggest doing a search on the OLEDBCommand.Parameters

Does anyone know how to retrieve a file saved in SQL Server. I know how to upload, but not how to download it to a place I choose(savefiledialog). Anyone know? Thanks!