Network traffic

[LucaBrasi]

I am curious about how Access 2000 handles network requests for data.
I have the data on a back-end server, and the front-end is installed
on the local machine. Now, lets say I have a select query ( call it
qry1) which has no filters and just displays all the records in the
table, and another query (qry2) which has a filter. Both are queries
on the same table of 5000 rows. If the qry2 filter matches only 1000
of the rows, is network traffic reduced? In other words, does qry2
just get all the rows from the table and then just display the ones
that match the filter, or do only the rows that match the filter
actually travel across the network ? Thanks for your help.

[Nick 'The Database Guy']

Re: Network traffic


LucaBrasi wrote:
[color=blue]
> I am curious about how Access 2000 handles network requests for data.
> I have the data on a back-end server, and the front-end is installed
> on the local machine. Now, lets say I have a select query ( call it
> qry1) which has no filters and just displays all the records in the
> table, and another query (qry2) which has a filter. Both are queries
> on the same table of 5000 rows. If the qry2 filter matches only 1000
> of the rows, is network traffic reduced? In other words, does qry2
> just get all the rows from the table and then just display the ones
> that match the filter, or do only the rows that match the filter
> actually travel across the network ? Thanks for your help.[/color]

No, requesting that a smaller recordset be returned will not reduce
network traffic; the reason for this is MS Access is not a true
client-server software solution. Let me explain. When your client
requests data from the back-end database the backend returns all the
rows in the table, they are then filtered by your client. I consider
this to be one of the main differences between MS Access and MS SQL
Server, which only returns the requested records, and thus will reduce
network traffic, quite dramatically in some cases, depending on the
query.

['69 Camaro]

Re: Network traffic

Hi, Nick.
[color=blue]
> When your client
> requests data from the back-end database the backend returns all the
> rows in the table, they are then filtered by your client.[/color]

That's a common misconception about Jet. If your tables are returning all
of the records in the table when the query doesn't specifically request all
of the rows (SELECT * FROM MyTable), then you need to place indexes on the
appropriate columns in the tables so that only the relevant records are
transferred across the network from the back end to the front end. Columns
involved in joins, criteria, and sorting are candidates for these indexes.
For a previous discussion on this topic, please see the following Web page:

http://groups.google.com/group/microsoft.public.access/browse_thread/thread/136cc58bf85b8e85/9be23e5e1a7eb151?&hl=en#9be23e5e1a7eb151

HTH.
Gunny

See http://www.QBuilt.com for all your database needs.
See http://www.Access.QBuilt.com for Microsoft Access tips and tutorials.
http://www.Access.QBuilt.com/html/ex...ributors2.html for contact
info.


"Nick 'The Database Guy'" <nickmcm@btinte rnet.com> wrote in message
news:1150891496 .415037.221550@ c74g2000cwc.goo glegroups.com.. .[color=blue]
>
> LucaBrasi wrote:
>[color=green]
>> I am curious about how Access 2000 handles network requests for data.
>> I have the data on a back-end server, and the front-end is installed
>> on the local machine. Now, lets say I have a select query ( call it
>> qry1) which has no filters and just displays all the records in the
>> table, and another query (qry2) which has a filter. Both are queries
>> on the same table of 5000 rows. If the qry2 filter matches only 1000
>> of the rows, is network traffic reduced? In other words, does qry2
>> just get all the rows from the table and then just display the ones
>> that match the filter, or do only the rows that match the filter
>> actually travel across the network ? Thanks for your help.[/color]
>
> No, requesting that a smaller recordset be returned will not reduce
> network traffic; the reason for this is MS Access is not a true
> client-server software solution. Let me explain. When your client
> requests data from the back-end database the backend returns all the
> rows in the table, they are then filtered by your client. I consider
> this to be one of the main differences between MS Access and MS SQL
> Server, which only returns the requested records, and thus will reduce
> network traffic, quite dramatically in some cases, depending on the
> query.
>[/color]

[paii, Ron]

Re: Network traffic


"Nick 'The Database Guy'" <nickmcm@btinte rnet.com> wrote in message
news:1150891496 .415037.221550@ c74g2000cwc.goo glegroups.com.. .[color=blue]
>
> LucaBrasi wrote:
>[color=green]
> > I am curious about how Access 2000 handles network requests for data.
> > I have the data on a back-end server, and the front-end is installed
> > on the local machine. Now, lets say I have a select query ( call it
> > qry1) which has no filters and just displays all the records in the
> > table, and another query (qry2) which has a filter. Both are queries
> > on the same table of 5000 rows. If the qry2 filter matches only 1000
> > of the rows, is network traffic reduced? In other words, does qry2
> > just get all the rows from the table and then just display the ones
> > that match the filter, or do only the rows that match the filter
> > actually travel across the network ? Thanks for your help.[/color]
>
> No, requesting that a smaller recordset be returned will not reduce
> network traffic; the reason for this is MS Access is not a true
> client-server software solution. Let me explain. When your client
> requests data from the back-end database the backend returns all the
> rows in the table, they are then filtered by your client. I consider
> this to be one of the main differences between MS Access and MS SQL
> Server, which only returns the requested records, and thus will reduce
> network traffic, quite dramatically in some cases, depending on the
> query.
>[/color]

If the table is indexed I believe Access will us the index to pull only the
records or pages requested, reducing network traffic.