I am looking for specific pieces of software across our network by querying the SCCM Database. My problem is that, for various reasons, sometimes I can search by the program's name and other times I need to search for a specific EXE.
When I run the query below, does it take 13 seconds to run if the where clause contains an AND, but it will run for days with no results if the AND is replaced with OR. I'm assuming it is doing this because I am not properly joining the tables. How can I fix this?
select vrs.Name0
FROM v_r_system as vrs
join v_GS_INSTALLED_SOFTWARE as VIS on VIS.resourceid = vrs.resourceid
join v_GS_SoftwareFile as sf on SF.resourceid = vrs.resourceid
where
VIS.productname0 LIKE '%office%' AND SF.Filename LIKE 'Office2007%'
GROUP BY vrs.Name0
Thanks!
Your LIKE
clause contains a wildcard match at the start of a string:
LIKE '%office%'
This prevents SQL Server from using an index on this column, hence the slow running query. Ideally you should change your query so your LIKE
clause doesn't use a wildcard at the start.
In the case where the WHERE
clause contains an AND
its querying based on the Filename
clause first (it is able to use an index here and so this is relatively quick) and then filtering this reduced rowset based on your productname0
clause. When you use an OR
however it isn't restricted to just returning rows that match your Filename
clause, and so it must search through the entire table checking to see if each productname0
field matches.