Hacking SPRoleDefinition SPRoleType in the database

If you are a Site Collection Administrator, SharePoint allows you to go to a Site Collection, Site Actions->Site Permissions->Permission Levels, then edit a permission level and delete it.

Some predefined Permission Levels (SPRoleDefinition) have a Type (SPRoleType) defined. This is not visible via the UI. However you can get this via Powershell as follows:

$web = Get-SPWeb your-web-url
$web.RoleDefinitions | Format-Table Id, Name, Type, Hidden -AutoSize

This gives output like the following:

        Id Name                       Type Hidden
        -- ----                       ---- ------
1073741829 Full Control      Administrator  False
1073741828 Design              WebDesigner  False
1073741827 Contribute          Contributor  False
1073741826 Read                     Reader  False
1073741825 Limited Access            Guest   True

Now, if you delete one of these such as the Contribute and then decide to recreate it, the type is now "None". There is no way to make the Type "Contributor".

This is all fine, but if you have some code that calls Microsoft.SharePoint.SPRoleDefinitionCollection.GetByType then your code is now broken.

To "resolve" (using the term very loosely as I do not know if there are any implications), I was able to restore this by hacking the database directly.

Essentially, I looked into the Roles table in the WSS_Content database, filtered on the WebId and RoleId and set the Type column directly in the database. Is it a good idea? Who knows? It seemed to work for me, but I do not know what I may have broken as a result of this.

User Profile Service Application Synchronization DB size

I have a SharePoint instance that is running out of disk space. Doing some poking around, I found that the User Profile Service Application Sync_DB has grown to almost 7GB. So, I ran the following SQL query to get more insight into what is going on:
exec sp_MSforeachtable @command1="EXEC sp_spaceused '?'"
Looking through the results I see that the culprits are as follows:

name	rows	reserved	data	index_size	unused
ObjectsInternal	3156618	2089728 KB	800296 KB	1288776 KB	656 KB
InstanceData	177997	4698144 KB	4697048 KB	296 KB	800 KB

I decided to take a peek inside these tables and it looks like there are thousands of objects created every day. So what are these and do they get cleared out any time?

I found a similar question asked: User Profile Service Application SyncDB Database Size. There is an response that is marked as an answer, but it merely leads us to recommended provisioning sizes of these databases to be medium to large (100GB to 1TB). There is no explanation why. This is quite bogus as I only have 75 profiles.

Argh!

I have posted a followup here: Moving the User Profile Service Application Synchronization Database