When we use the ASP built-in ADO component to program database programming, we usually open a connection at the beginning of the script, and close it at the script, but in large scripts, in most cases, the connection is more than it. It is much longer than the time you need to open. Therefore, in order to save server resources, the connection should be closed as much as possible to release the resources occupied by the connection, which close the record set without closing the technique of the recordset is called the disconnected record set, this recordset itself is called a disconnected record set.
Below we will explain this technique by an example (northwind.mdb is a database comes with Microsoft Access, file adovbs.inc can be found under C: / Program Files / Common files / system / ado):
<% @Language = VBScript%>
<%
Response.expires = 0
DIM CNN, OBJRS, STROUT, STRQ, STRC
Strc = "driver = {Microsoft Access Driver (* .mdb)}; dbq =" & Server.mappath ("/ asp24")
& "/Northwind.mdb;"
'establish connection
SET CNN = Server.createObject ("AdoDb.Connection")
CNN.Open STRC
'Creating a RecordSet object
Set objrs = server.createObject ("adoDb.recordset")
Objrs.cursorLocation = aduseclient
Objrs.cursortype = adopenStatic
Objrs.lockType = AdlockOptimistic
STRQ = "SELECT shipper ID, company name, phone FROM shipper"
Objrs.open strq, CNN,, AdcmdText
Set objrs.activeConnection = Nothing 'Disconnect record set
CNN.Close 'Close connection
SET CNN = Nothing
Response.write ""
'Use the disconnected record set below
Do While (not objrs.eof)
Strout = Objrs ("Continental ID") & "," & Objrs ("Company Name") & "," & Objrs ("Phone")
Response.write Server.htmlencode (Strout) & ""
Objrs.movenext
Loop
Response.write "
Prepare new or insert records: "
'If you need to update the database, you must re-establish the connection.
SET CNN = Server.createObject ("AdoDb.Connection")
CNN.Open STRC
Set objrs.activeConnection = CNN
Objrs.filter = "Company Name = 'Wu Feng'"
IF objrs.eof kil
Objrs.addnew
ObJRS ("Company Name") = "Wu Feng"
ObJRS ("Phone") = "571-7227298"
Objrs.Updateresponse.write "Added.
"
Else
ObJRS ("Phone") = "571-7227071"
Response.write "Update is existent."
Objrs.update
END IF
Set objrs.activeConnection = Nothing
CNN.Close
SET CNN = Nothing
Objrs.close
Set objrs = Nothing
Response.write ""
%>
