Speeding up page load
I have a 2D array that is filled with data from a database which is then used within a while loop with another sql query. For each item in the while loop i'm checking for certain items within the 2d array using a for loop.
How can i speed this up because the items within the while loop are within 1000 - 2000 items and it takes 3 - 4 seconds to load the webpage.
Here is my 2d array -
'MultiDimensional Array
Dim permissionsArray()
Dim permissionsCount
connectionstring = obj_ADO.getconnectionstring
Increment = 1
set c = CreateObject("ADODB.Connection")
set r = CreateObject("ADODB.R开发者_JS百科ecordset")
c.open connectionstring
SQL = "select Count(P_Name) as permissionsCount from l_objectpermission inner join A_Permission on op_permissionID = P_permissionID"
r.open SQL, c
permissionsCount = r("permissionsCount")
r.close
c.close
Set objCon = CreateObject("ADODB.Connection")
Set objRS = CreateObject("ADODB.Recordset")
objCon.Open connectionstring
SQL = "select OP_ObjectID, P_Name from l_objectpermission inner join A_Permission on op_permissionID = P_permissionID order by P_Name"
objRS.open SQL, objCon
Redim permissionsArray(2, permissionsCount)
if not objRS.EOF then
objRS.MoveFirst
while not objRS.EOF
permissionsArray(0, increment) = objRS("OP_ObjectID")
permissionsArray(1, increment) = objRS("P_Name")
objRS.MoveNext
Increment = Increment + 1
wend
objRS.close
objCon.close
end if
and inside my while loop is -
Page_ID = objRS("P_PageID")
for i = 0 to (permissionsCount)
if permissionsArray(0, i) = Page_ID then
%>
<li style="height: 2px;">
<%=permissionsArray(1,i)%>
</li>
</br>
<%
end if
next
%>
</div></center></td>
Here is your bottle neck:
if not objRS.EOF then
objRS.MoveFirst
while not objRS.EOF
If all you want is a 2 dimensional array, then you would use Recordset.GetRows() instead
'MultiDimensional Array
Dim permissionsArray
Dim permissionsCount
connectionstring = obj_ADO.getconnectionstring
Set c = Server.CreateObject("ADODB.Connection")
Set r = Server.CreateObject("ADODB.Recordset")
r.CursorLocation = 2 'adUseServer
c.open connectionstring
c.CursorLocation = 2 'adUseServer
SQL = "select OP_ObjectID, P_Name from l_objectpermission inner join A_Permission on op_permissionID = P_permissionID order by P_Name"
Set r = Server.CreateObject("ADODB.Recordset")
r.CursorLocation = 2 'adUseServer
r.Open SQL, c, 0, 1 'adOpenForwardOnly, adLockReadOnly
If r.BOF or r.EOF Then
r.close()
Set r = Nothing
Else
permissionsArray = r.GetRows()
permissionsCount = UBound(permissionsArray, 2) + 1
r.Close()
Set r = Nothing
End If
c.Close()
Set c = Nothing
References:
http://www.learnasp.com/advice/whygetrows.asp
http://www.w3schools.com/ado/met_rs_getrows.asp
http://www.devguru.com/technologies/ado/quickref/recordset_getrows.html
Assuming the issue has to do with the ADODB side of things, and not the fact that you are trying to render 2000 <LI>'s...
It generally is a good practice to reuse your ADODB.Connection. Closing the connection and then reopening it is probably costing you a slight amount of performance.
You should also specify the RecordSet properties (before the RecordSet is opened):
CursorLocation: adUseServer[2] runs the cursor on the server; the server streams the recordset to the client in chunks, allowing the client to start processing sooner, rather than waiting until the entire set is received; also, the memory is managed on the server so you won't have memory issues on the client if lots of people are hitting the page at the same time; http://msdn.microsoft.com/en-us/library/ee252442(v=bts.10).aspx
LockType: adLockReadOnly[1] indicates read-only records where the data cannot be altered; if you are not altering the data, this should be the fastest; http://msdn.microsoft.com/en-us/library/ee252458(v=BTS.10).aspx
CursorType: adOpenForwardOnly[0] Specifying this value opens a forward-only-type cursor. This CursorType is identical to a static cursor, except that you can only scroll forward through records. This improves performance when only one pass through a Recordset is needed. http://msdn.microsoft.com/en-us/library/ee252445(v=BTS.10).aspx
You should also get rid of the "count" query...unless you need it for some other reason. Otherwise, you can set the value of permissionsCount = UBOUND(permissionsArray)...i think...it's been a long time since i've done any vbscript!
SQL = "select OP_ObjectID, P_Name from l_objectpermission inner join A_Permission on op_permissionID = P_permissionID order by P_Name"
Set rs = Server.CreateObject("ADODB.RecordSet")
rs.CursorLocation = 2 'adUseServer
rs.LockType = 1 'adLockReadOnly
rs.CursorType = 0 'adOpenForwardOnly
rs.ActiveConnection = c
rs.Open SQL
If NOT rs.EOF Then
permissionsArray = rs.GetRows()
End If
rs.close()
Set rs = Nothing
c.Close()
Set c = Nothing
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