How do you create an ADODB disconnected recordset in a VB.NET Windows application?
I'm using an OLEDB connection to a Sybase database, with ADODB.dll file version 7.10.6070.0 (which comes from the Sybase 12.5 package). I need to be able to open a connection, use a command object to fill a recordset from a stored procedure, then close the connection and pass back a disconnected recordset. My attempts so far fail as every time I close the connection, my recordset also closes (which means it is not disconnected).
Is there a property I must set somewhere to indicate that the recordset should be disconnected? I cannot set Recordset.ActiveConnection = False because I get an exception ("Cannot change the ActiveConnection property of a Recordset object which has a Command object as its source."). I do set the Command.ActiveConnection = False, but that doesn't stop the re开发者_运维百科cordset from closing as soon as I close the connection object.
Snippet:
Dim conn as New ADODB.Connection()
conn.Open("connectionString", "UserID", "Password")
Dim cmd as New ADODB.Command()
' Set some parameters on the command.
cmd.ActiveConnection = conn
cmd.CommandText = "StoredProcedureName"
cmd.CommandType = ADODB.CommandTypeEnum.adCmdStoredProc
Dim rs as New ADODB.Recordset()
rs.Open(cmd)
Dim clonedRS as ADODB.Recordset = rs.Clone() ' one attempt to disconnect recordset
rs.Close() ' Does not close cloned recordset
cmd.ActiveConnection = Nothing ' another try at disconnecting recordset
conn.Close() ' Always closes the recordset, even the cloned one
return clonedRS ' Sadly, this is closed now.
I don't know if this will solve your problem, but I did a Google search and came upon this article Disconnect an ADO Recordset generated from a Command object, which you might be able to use to modify your code as follows:
Dim conn as New ADODB.Connection()
conn.Open("connectionString", "UserID", "Password")
Dim cmd as New ADODB.Command()
' Set some parameters on the command.
cmd.ActiveConnection = conn
cmd.CommandText = "StoredProcedureName"
cmd.CommandType = ADODB.CommandTypeEnum.adCmdStoredProc
Dim rs As ADODB.Recordset
With rs
.CursorLocation = adUseClient
.Open cmd, CursorType:=adOpenStatic, Options:=adCmdStoredProc
Set .ActiveConnection = Nothing
End With
Dim clonedRS As ADODB.Recordset = rs
Set cmd = Nothing
conn.Close()
rs.Close()
Set conn = Nothing
Set rs = Nothing
Return clonedRS
There's another example from 4GuysFromRolla Using Disconnected Recordsets that has the same approach.
EDIT
Fleshed out the example.
you could try something along this line
Set cmd = New ADODB.command
With cmd
.ActiveConnection = "your connection"
.CommandText = "your proc or ssql"
.CommandType = adCmdStoredProc
' .parameter.append create whether param you need
End With
Set rs = New ADODB.recordset
With rs
.cursorlocation = adUseClient
.cursortype = adOpenStatic
.locktype = adLockBatchOptimistic
Set rs.Source = cmd 'this is the key
.Open
.ActiveConnection = Nothing
End With
' do what ever you need next
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