Can anyone explain me this please

Hi,
Can anyone explain me what the persons means by
saying: "multiple files"... how do i do this'
If your database is very large and very busy, multiple
files can be used to increase performance. Here is one
example of how you might use multiple files. Let's say you
have a single table with 10 million rows that is heavily
queried. If the table is in a single file, such as a
single database file, then SQL Server would only use one
thread to perform a read of the rows in the table. But if
the table were divided into three physical files (all part
of the same filegroup), then SQL Server would use three
threads (one per physical file) to read the table, which
potentially could be faster. In addition, if each file
were on its own separate physical disk or disk array, the
performance gain would even be greater.
Thanxs for your patience,
CC
What did you mean by
> But if the table were divided into three physical files (all part
> of the same filegroup) ?
You can place heavily accessed tables and the nonclustered indexes belonging
to those tables on different filegroups. This will improve performance, due
to parallel I/O if the files are located on different physical disks
"C" <anonymous@.discussions.microsoft.com> wrote in message
news:06a801c3ce01$93fcc010$a101280a@.phx.gbl...
> Hi,
> Can anyone explain me what the persons means by
> saying: "multiple files"... how do i do this'
> If your database is very large and very busy, multiple
> files can be used to increase performance. Here is one
> example of how you might use multiple files. Let's say you
> have a single table with 10 million rows that is heavily
> queried. If the table is in a single file, such as a
> single database file, then SQL Server would only use one
> thread to perform a read of the rows in the table. But if
> the table were divided into three physical files (all part
> of the same filegroup), then SQL Server would use three
> threads (one per physical file) to read the table, which
> potentially could be faster. In addition, if each file
> were on its own separate physical disk or disk array, the
> performance gain would even be greater.
> Thanxs for your patience,
> C|||Actually, what your paragraph is talking about is putting several data files
in a single filegroup..
You can use SEM to add more data files to the Primary filegroup.
AFTER you have multiple files in the filegroup, THEN load the data... SQL
Server will stripe the data across all of the data files. and when you do a
query, SQL will automatically use parallel IO Threads ( one for each file)
to get the data..
This can allow better performance for a single user's query....
If all of the files are in a single raid array, the rule of thumb is not
more than 8 files, and not more than one file per hard drive... So if you
are using a 4 drive raid array, create 4 data files...
Wayne Snyder, MCDBA, SQL Server MVP
Computer Education Services Corporation (CESC), Charlotte, NC
www.computeredservices.com
(Please respond only to the newsgroups.)
I support the Professional Association of SQL Server (PASS) and it's
community of SQL Server professionals.
www.sqlpass.org
"C" <anonymous@.discussions.microsoft.com> wrote in message
news:06a801c3ce01$93fcc010$a101280a@.phx.gbl...
> Hi,
> Can anyone explain me what the persons means by
> saying: "multiple files"... how do i do this'
> If your database is very large and very busy, multiple
> files can be used to increase performance. Here is one
> example of how you might use multiple files. Let's say you
> have a single table with 10 million rows that is heavily
> queried. If the table is in a single file, such as a
> single database file, then SQL Server would only use one
> thread to perform a read of the rows in the table. But if
> the table were divided into three physical files (all part
> of the same filegroup), then SQL Server would use three
> threads (one per physical file) to read the table, which
> potentially could be faster. In addition, if each file
> were on its own separate physical disk or disk array, the
> performance gain would even be greater.
> Thanxs for your patience,
> C