Is it possible to query the system databases in SQL server without using the names?

Question

When doing a query over several databases in SQL server (2005+) I find it sometimes necesary to exclude the system database (master, model, tempdb, msdb and distribution)

Is there any OTHER way to filter these besides

where name not in (''master', 'model', 'tempdb', 'msdb', 'distribution')

I've looked at sys.databases and master.dbo.sysdatabases (not the same!)

[UPDATE] an example query which I use to look for databases that have logshipping enabled

select d.name, p.last_backup_date, s.secondary_server, s.secondary_database
from sys.databases d
    left outer join msdb..log_shipping_primary_databases p on p.primary_database = d.name
    left outer join msdb..log_shipping_primary_secondaries s on s.primary_id = p.primary_id
where name not in ('model','master','tempdb','distribution','msdb')
order by d.name

[UPDATE] This seems to be the 'least bad' way, unless someone else has a better way?

SELECT * FROM 
master.sys.databases AS dtb 
WHERE (dtb.database_id < 5 or dtb.is_distributor = 1)

Answer 1

There is no safe means beyond searching on the name. If you only wanted to filter out the four main databases (master, model, msdb, tempdb), you can safely filter on DBID > 4. However the distribution database will get a DBID like a normal database and thus you cannot rely on its DBID.

Answer 2

I ran SQL Profiler and refreshed the system databases node in management studio. It uses the query

...FROM
master.sys.databases AS dtb
WHERE
(CAST(case when dtb.name in ('master','model','msdb','tempdb') 
then 1 else dtb.is_distributor end AS bit)=1)

So I guess you could combine the dbid and is_distributor checks.