I'm researching defragmenting databases and it seems the following SQL statement is what I'm looking for:
ALTER INDEX ALL ON mytablename REBUILD WITH(ONLINE = ON)
When I pull the info from
sys.dm_db_index_physical_stats, I see the percents are very high - 70, 80 and 90 percent (!). So that tells me I want a
REBUILD, and not a
I have a few question before executing these
- Can it be ran while processes are using the database? (
ONLINE = ONtells me yes, but I want to confirm it won't crash anything.) Or is it better to run when it's not in use?
- I read
REBUILDmakes things run slower. Is that just while the indexes are being rebuilt? (or forever after)
- How long will it take to rebuild all indexes / or rather each one?
- Are there any side effects or other info that I need to be aware of? This is production/live database.
EDIT: And finally, what is the best way to go about rebuilding it? Looping through all the objects with a percentage of greater than 30? Or?