Hi there,
i´m in trouble with my mind and want the same of you as from now :)
My topic belongs to WebDAV-Performance access where i currently work on.
Access via WebDAV has one particular difference when we comparing dirctly with logicalDOC. By web we getting a much more straight forward path to a folder structure (and his content) using a unique number. Here its ld_menu.ld_id. The consequence is, that we can fairly fast accessing a appropriate folder by this approach. Indexing is adequate for use.
WebDAV has no such feasability as we have no unqique id or something else for using a efficient index-access. An easy example:
/ (Root)
/My Images
/Documents
-|/...
-|/Bills/Something other/
-|/...
If we want going into the folder Bills(because we have something for pay and dont know the right folder at all) by starting over the root, we have to asking the DB six times for getting the right folder:
/
/Documents
/Documents/Bills
So we have a much more semantically access as an technically (as with IDs) procedure. The Problem is now, that we riding into a performance-farce when we looking at a use-case of 60.000 Documents anf folders or much more.
What solutions exists?
1. No Changes
2. Indexing FolderNames
3. FolderTable
1) No Changes are good for us. Because we have to change nothing and can drinking a lot of whisky at the evening for relaxing and so on... But costumers/users getting rather angry when they have thousends
of documents to mange. Taking again the example above, we have to take 6(N^2 where N is the number of folders to the target-folder) times a full table scan on the ld_menu and on index-access. We need this count as we have getting at first the right folder (e.g. /Documents) and then the documents within the folder.
2) Indexing the name of the folder(ld_menu) attribute. Its on way, but ever DML on foldernames will be driving into a index-change which can cause transactional errors or performance-issues. I say, it can but its one way we can go without big changes and see in the future (or by costumer reports) whether this way turns into a much more inconvenienced situation.
3) Third possibility is to create a new table that holds ever folder path - and i mean an absolutly path - in the table. For Instance:
______PATH_____________________________________ID____
/My Images ....................................1
/My Images/Image Album I ......................2
/My Images/Image Album I/thumbnails ...........3
/Documents ....................................4
Every document is referencing to one ID. By WebDAV(and the usage is only for webdav or CIFS) we can passing the current path ino a sql-query and the db must take one FTS. The problems here are very wide-spreaded. For example, if we want to changing a folder that is positioned upon the middle (Image Album I) we have changing ID 2 and 3 for stay clear in the database.
Therefore i suggest the second point.
Best Regards
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