SharePoint Associated groups

When you create a new sub-site in SharePoint, and choose the "Use Unique Permissions" option, three groups are created at the site-collection level: Owners, Members & Visitors. These groups are "associated" to the sub-site that you've just created.

But what does "associated" actually mean?

First, I misled you a bit - the names of the groups are actually SiteName Owners, SiteName Members & SiteName Visitors (where SiteName is the name of the sub-site you're creating).

Next they all have a nice link in their description, directing you to the sub-site.

More interesting, those three groups get some permissions on the sub-site.

The less obvious "associations" are the fact that those groups will appear in the Quick Launch area when you go to the "People and Groups" section of the site. Also, if you delete the sub-site, the groups will be removed from the site-collection.

Lastly, when you add a user to the site, you can either assign the user an explicit permission level, or you can add her to onw of the associated groups of the site.

That's quite a lot of meaning for a single word. Let look a bit deeper into each meaning:

Title & Description: This is just some basic naming policy used by SharePoint. The SiteName is validated, the group type is appended, the description is generated with a link. Nothing fancy here.

Permissions: The permissions are obtained by assigning permission levels to each group. Again, nothing too interesting.

Quick Launch: The list of groups that appear in the Quick Launch is retained in the AssociatedGroups property of the SPWeb. This list can also be updated by modifying the vti_associategroups key in the AllProperties property of SPWeb. Setting a group as the AssociatedMemberGroup, AssociatedVisitorGroup or AssociatedOwnerGroup automatically adds the group to the list of AssociatedGroups. These properties can be also updated by modifying the vti_associatemembergroup, vti_associatevisitorgroup & vti_associateownergroup keys in the AllProperties property of SPWeb. These three properties are also reflected in the "Set up Groups" page of the sub-site.

Auto deletion: This issue is a bit more complex. When using the SharePoint UI, or when calling CreateDefaultSharePointGroups methods of SPWeb, this behavior is implemented automatically. However, creating a group, and even associating it with a site, doesn't reproduce it. Only after using Lutz Roeder's .Net Reflector, and examining the CreateDefaultSharePointGroups method, I've found that you need to add the group's ID to the vti_createdassociategroups key in AllProperties.

Adding Users: When adding a user to a sub-site, only the groups listed in AssociatedGroups are listed as possible groups for the new user.

SqlCE doesn't support TRUNCATE TABLE

Not long ago, I modified a piece of code to use SqlCE as a data store. The older code was using OleDb to access an MS Access file. As part of the modifications, our team did a general overview of much of the data access code. We did many changes, more than I can even number. Here is a partial list: Review of table keys, indices and restrictions. Usage of IDbCommand instead of SQL string statements. Removed legacy object model. Replaced consecutive DELETE and INSERT statements with UPDATE. and so on. A few days ago, I noticed some delay in the data layer. This was nothing new - we process a huge amount of data - but since the many improvements, what used to be fast might now appear slow compared to the optimized code. After some search I've come up to a method that clears a many tables in the database. Something along the lines of:

using (IDbCommand cmd = DAL.GetClearTableCommand(tablename))
{
    // cmd.CommandText == "DELETE FROM " + tablename
    cmd.ExecuteNonQuery();
}

This of course, is nothing fancy or special. My thought was, instead of performing a DELETE statement, why not use the TRUNCATE TABLE statement, which is faster and more efficient. To my surprise, changing the GetClearTableCommand() method to return a TRUNCATE TABLE statement results in an parsing exception. After some research, I've found that the TRUNCATE TABLE statement is not supported/implemented in SqlCE. Much to my disappointment, I will have to leave the DELETE statement in place, until I find a faster solution.