RE: Paging and permissions

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Instead of serializing the articles, you only need their IDs. Using

    $sql .= ' where id in (' . implode(',', $ids) . ')';

you can load the data for a page of results in a single query. Storing the
IDs is much cheaper than the articles.

If the permissions are fairly static (i.e. access for user X to article Y
doesn't change every two minutes) you could create a calculated permission
table as a many-to-many between user and article. Here's the logic flow for
a query:

1. Run the query to find matching article IDs
2. Load permissions from table for all IDs
3. For each article without a calculated permission, calculate it and insert
a row (do a batch insert to save time)

If you flag the query in the middle tier as having been processed as above,
you can join to the calculated permissions each time you need another page.
The downside is that the code that runs the queries has to operate in two
modes: raw and joined to the permissions. If most users end up querying for
all articles, the table could grow. Plus you need to purge rows any time the
permissions for an article/user changes which could get fairly complicated.

David

-----------
 
Storing only the IDs is way cheaper than storing the entire resultset, and
I'd been thinking along the same lines. Getting a complete list of valid IDs
in the first place is turning out to be a different matter. The permissions
for article/user aren't that straight-forward, and in fact the most common
permissions are group/category and group/container, where an article can be
assigned to one or more category/containers. Using a temporary permission
table could be the solution. Thanks.

Cheers
Arno



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