\Program Files\Microsoft Data Access SDK\Docs\ado260.chm
Там есть:
Connection object(ADO)-->Connection Object Properties, Methods, and Events
-->State Property-->Returns a Long value that can be an ObjectStateEnum value.
-->
Constant Value Description
adStateClosed 0 Indicates that the object is closed.
adStateOpen 1 Indicates that the object is open.
adStateConnecting 2 Indicates that the object is connecting.
adStateExecuting 4 Indicates that the object is executing a command.
adStateFetching 8 Indicates that the rows of the object are being retrieved