database maintenance for companies that run 24/7

For a company like an airline that runs 24/7 and the database is always
being accessed and they can't shut down, how do they do maintenance on their
databases? How do they do things like defrag or rebuild indexes or shrink
files?
Do they have two databases and they switch back and forth?
Thanks,
Dan
> For a company like an airline that runs 24/7 and the database is always
> being accessed and they can't shut down, how do they do maintenance on
their
> databases?
Clustering, perhaps? We use it here...
Aaron Bertrand
SQL Server MVP
http://www.aspfaq.com/
|||Generally they use dbcc indexdefrag instead of dbcc dbreindex, you just need to be more diligent with its application.
It also becomes critical to size the database correctly so that it does not go offline for database growths/shrinks.
|||They do what they have to based on their specific requirements. Almost no
one that is in a 24 x 7 will be doing any shrinking of files and it should
rarely be done anyway. If it's truly 24 x 7 then DBREINDEX may not be an
option and INDEDXDEFRAG might be the way to go. It is impossableto go into
enough detail of how to maintain a 24 x 7 operation in a newsgroup. If you
have this type of requirement and are asking these questions I would highly
recommend you hire a qualified consultant.
Andrew J. Kelly SQL MVP
"Dan" <ddonahue@.archermalmo.com> wrote in message
news:%23T1z%23uaPEHA.252@.TK2MSFTNGP10.phx.gbl...
> For a company like an airline that runs 24/7 and the database is always
> being accessed and they can't shut down, how do they do maintenance on
their
> databases? How do they do things like defrag or rebuild indexes or shrink
> files?
> Do they have two databases and they switch back and forth?
> Thanks,
> Dan
>
|||Good points. I was thinking more along the lines of applying security
fixes, windows update, etc.
Aaron Bertrand
SQL Server MVP
http://www.aspfaq.com/
"Andrew J. Kelly" <sqlmvpnoooospam@.shadhawk.com> wrote in message
news:#Qh#aDbPEHA.4036@.TK2MSFTNGP12.phx.gbl...
> They do what they have to based on their specific requirements. Almost
no
> one that is in a 24 x 7 will be doing any shrinking of files and it should
> rarely be done anyway. If it's truly 24 x 7 then DBREINDEX may not be an
> option and INDEDXDEFRAG might be the way to go. It is impossableto go
into
> enough detail of how to maintain a 24 x 7 operation in a newsgroup. If you
> have this type of requirement and are asking these questions I would
highly
> recommend you hire a qualified consultant.
|||Ken and Andrew,
So, even though INDEXDEFRAG isn't as efficient as DBREINDEX, I guess it is
sufficient. Isn't there fragmentation that also happens to the data on the
disk as well as to the indexes? How would you handle that kind of
fragmentation?
Dan
"Andrew J. Kelly" <sqlmvpnoooospam@.shadhawk.com> wrote in message
news:%23Qh%23aDbPEHA.4036@.TK2MSFTNGP12.phx.gbl...
> They do what they have to based on their specific requirements. Almost
no
> one that is in a 24 x 7 will be doing any shrinking of files and it should
> rarely be done anyway. If it's truly 24 x 7 then DBREINDEX may not be an
> option and INDEDXDEFRAG might be the way to go. It is impossableto go
into
> enough detail of how to maintain a 24 x 7 operation in a newsgroup. If you
> have this type of requirement and are asking these questions I would
highly[vbcol=seagreen]
> recommend you hire a qualified consultant.
> --
> Andrew J. Kelly SQL MVP
>
> "Dan" <ddonahue@.archermalmo.com> wrote in message
> news:%23T1z%23uaPEHA.252@.TK2MSFTNGP10.phx.gbl...
> their
shrink
>
|||Depending on what you mean by 'as efficient' (disk space, log space, cpu
usage, IOs, elapsed time), I didn't design INDEXDEFRAG to be more efficient
that DBREINDEX - it's meant to be an online alternative to rebuilding
indexes. You should read the whitepaper below for more details.
http://www.microsoft.com/technet/pro.../ss2kidbp.mspx
Regards.
Paul Randal
Dev Lead, Microsoft SQL Server Storage Engine
This posting is provided "AS IS" with no warranties, and confers no rights.
"Dan" <ddonahue@.archermalmo.com> wrote in message
news:#FdM04bPEHA.556@.tk2msftngp13.phx.gbl...
> Ken and Andrew,
> So, even though INDEXDEFRAG isn't as efficient as DBREINDEX, I guess it
is[vbcol=seagreen]
> sufficient. Isn't there fragmentation that also happens to the data on the
> disk as well as to the indexes? How would you handle that kind of
> fragmentation?
> Dan
> "Andrew J. Kelly" <sqlmvpnoooospam@.shadhawk.com> wrote in message
> news:%23Qh%23aDbPEHA.4036@.TK2MSFTNGP12.phx.gbl...
> no
should[vbcol=seagreen]
an[vbcol=seagreen]
> into
you[vbcol=seagreen]
> highly
always
> shrink
>
|||Thanks. I will.
"Paul S Randal [MS]" <prandal@.online.microsoft.com> wrote in message
news:uRVJRJcPEHA.252@.TK2MSFTNGP10.phx.gbl...
> Depending on what you mean by 'as efficient' (disk space, log space, cpu
> usage, IOs, elapsed time), I didn't design INDEXDEFRAG to be more
efficient
> that DBREINDEX - it's meant to be an online alternative to rebuilding
> indexes. You should read the whitepaper below for more details.
>
http://www.microsoft.com/technet/pro.../ss2kidbp.mspx
> Regards.
> --
> Paul Randal
> Dev Lead, Microsoft SQL Server Storage Engine
> This posting is provided "AS IS" with no warranties, and confers no
rights.[vbcol=seagreen]
> "Dan" <ddonahue@.archermalmo.com> wrote in message
> news:#FdM04bPEHA.556@.tk2msftngp13.phx.gbl...
> is
the[vbcol=seagreen]
Almost[vbcol=seagreen]
> should
> an
> you
> always
on
>