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Exporting data while people are using the site?

I'm exporting a large file from a large Production database (SQL).

Users are currently updating and inserting new records.

Does the export take a snapshot of the data when it starts ? or will
it freeze the database so all udpates/inserts happen after the export
completes?

Also, how do I get the delta of data that wasn't exported, if I want
to get the difference the next day?

Thank yoU!!!
Jul 20 '05 #1
4 1881
"Angel Cat" <ki***********@hotmail.com> wrote in message
news:9b**************************@posting.google.c om...
I'm exporting a large file from a large Production database (SQL).
Users are currently updating and inserting new records.
Is it 24hr updating or is there a break during the night?
Does the export take a snapshot of the data when it starts ? or will
it freeze the database so all udpates/inserts happen after the export
completes?
Snapshot.
Also, how do I get the delta of data that wasn't exported, if I want
to get the difference the next day?


Comparitive reporting on some key field to provide stats.
OTOH these import tasks can be automated and scheduled.
If the database shows no activity at 3:00am daily, do it then.

Jul 20 '05 #2
THe database is in use 24 hours a day. I need to take a dump of the
data and and make some updates but what happens when a user is updting
while I take a dump. Does DTS freeze the data when I'm exporting?

ALso, is there a way I can take the difference easily?

Thank yoU!

"mountain man" <hobbit@southern_seaweed.com.op> wrote in message news:<38******************@news-server.bigpond.net.au>...
"Angel Cat" <ki***********@hotmail.com> wrote in message
news:9b**************************@posting.google.c om...
I'm exporting a large file from a large Production database (SQL).
Users are currently updating and inserting new records.


Is it 24hr updating or is there a break during the night?
Does the export take a snapshot of the data when it starts ? or will
it freeze the database so all udpates/inserts happen after the export
completes?


Snapshot.
Also, how do I get the delta of data that wasn't exported, if I want
to get the difference the next day?


Comparitive reporting on some key field to provide stats.
OTOH these import tasks can be automated and scheduled.
If the database shows no activity at 3:00am daily, do it then.

Jul 20 '05 #3
"Angel Cat" <ki***********@hotmail.com> wrote in message
news:9b**************************@posting.google.c om...
THe database is in use 24 hours a day. I need to take a dump of the
data and and make some updates but what happens when a user is updting
while I take a dump. Does DTS freeze the data when I'm exporting?
Effectively it does a snapshot.
ALso, is there a way I can take the difference easily?
The quantitative difference can be approximated in the first
instance by publishing the rowcount of the table "as at snapshot"
as distinct from the rowcount of the realtime SQL table which
can be easily obtained dynamically between loads. This will
represent (net) rows to be added/deleted.

Operationally this will imply part of the export process
will be to write the "last record included" type of thing
to some local table.

The quantitative differences are more difficult issues to deal
with but obviously you need to decide what elements of the
data you wish to keep track of during inter-load build-ups.
These you can add to the rowcount info if/when req'd.

Another idle thought here includes a master-publication
register accessible to the distribution group (who are getting
your export file) which is updated at every publication with
relevant information, and coupled with a realtime query into
SQL to compare nowtime with last publication.

Thank yoU!

"mountain man" <hobbit@southern_seaweed.com.op> wrote in message

news:<38******************@news-server.bigpond.net.au>...
"Angel Cat" <ki***********@hotmail.com> wrote in message
news:9b**************************@posting.google.c om...
I'm exporting a large file from a large Production database (SQL).
Users are currently updating and inserting new records.


Is it 24hr updating or is there a break during the night?
Does the export take a snapshot of the data when it starts ? or will
it freeze the database so all udpates/inserts happen after the export
completes?


Snapshot.
Also, how do I get the delta of data that wasn't exported, if I want
to get the difference the next day?


Comparitive reporting on some key field to provide stats.
OTOH these import tasks can be automated and scheduled.
If the database shows no activity at 3:00am daily, do it then.

Jul 20 '05 #4
Angel Cat,

It was my understanding that SQL 7 and 2000 have a snapshot of the data "as
of" the end time of the databases.
If you start your backup at 6pm and users are inserting and updating, and
your database backup finishes at 6:30pm, your backup will be as of 6:30pm.

MSSQL 6.5 had a snapshot of the data at 6pm. Assuming the example above.

Oscar....

"Angel Cat" <ki***********@hotmail.com> wrote in message
news:9b**************************@posting.google.c om...
I'm exporting a large file from a large Production database (SQL).

Users are currently updating and inserting new records.

Does the export take a snapshot of the data when it starts ? or will
it freeze the database so all udpates/inserts happen after the export
completes?

Also, how do I get the delta of data that wasn't exported, if I want
to get the difference the next day?

Thank yoU!!!

Jul 20 '05 #5

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