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access thread: Back-End on the Web Server


Message #1 by "George Oro" <george@c...> on Sat, 1 Jun 2002 17:35:05 +0400
Hi Guys,

Just a thought!

I have a prospective project which required to access the database wherever country the user is.

The scenario is, 5 user's has it's own Laptop and used to travel around the world except for the Master Data Entry Operator using
normal pc at the base.

The main objective is, wherever country the 5 user is, they can access the database anytime by establishing the connection to the
Back-End Server and open the Interface on their laptop and access all the features of the application. Furthermore, who ever do some
updates, the changes must reflect same as you are in the local area network.

Is Access can achieved the above requirements? Any idea is welcome and highly appreciated.


Cheers,
George




Message #2 by "Randy Cornish" <rlcornish@c...> on Sun, 2 Jun 2002 00:38:53
Not enough information to make a quality suggestion.  When you 
say "Interface", is that a VB app, an Access MDB or a browser interface?  
Another way to ask that is: Will the user will have the application 
installed on their laptop?

How much data transfer is involved?

Is Microsoft WTS (Windows Terminal Server) an option?

What baud rate can be assumed?  (It is probably best to design as if the 
user had to work over a 2400 baud line, especially for International 
situations.

Is using SQL Server 2000 and its support for XML an option?


R

> 
Hi Guys,

Just a thought!

I have a prospective project which required to access the database 
wherever country the user is.

The scenario is, 5 user's has it's own Laptop and used to travel around 
the world except for the Master Data Entry Operator using
normal pc at the base.

The main objective is, wherever country the 5 user is, they can access 
the database anytime by establishing the connection to the
Back-End Server and open the Interface on their laptop and access all the 
features of the application. Furthermore, who ever do some
updates, the changes must reflect same as you are in the local area 
network.

Is Access can achieved the above requirements? Any idea is welcome and 
highly appreciated.


Cheers,
George




Message #3 by "George Oro" <george@c...> on Sun, 2 Jun 2002 08:56:00 +0400
Randy,
Thanks for your reply, here's the answers of your doubt:
1. Interface= Access2000
2. Yes, each laptop has the interface.
3. Around 20-30 thousand records (4 Tables)

What is baud rate by the way?


Cheers,
George


-----Original Message-----
From: Randy Cornish [mailto:rlcornish@c...]
Sent: Sunday, June 02, 2002 12:39 AM
To: Access
Subject: [access] Re: Back-End on the Web Server


Not enough information to make a quality suggestion.  When you 
say "Interface", is that a VB app, an Access MDB or a browser interface?  
Another way to ask that is: Will the user will have the application 
installed on their laptop?

How much data transfer is involved?

Is Microsoft WTS (Windows Terminal Server) an option?

What baud rate can be assumed?  (It is probably best to design as if the 
user had to work over a 2400 baud line, especially for International 
situations.

Is using SQL Server 2000 and its support for XML an option?


R

> 
Hi Guys,

Just a thought!

I have a prospective project which required to access the database 
wherever country the user is.

The scenario is, 5 user's has it's own Laptop and used to travel around 
the world except for the Master Data Entry Operator using
normal pc at the base.

The main objective is, wherever country the 5 user is, they can access 
the database anytime by establishing the connection to the
Back-End Server and open the Interface on their laptop and access all the 
features of the application. Furthermore, who ever do some
updates, the changes must reflect same as you are in the local area 
network.

Is Access can achieved the above requirements? Any idea is welcome and 
highly appreciated.


Cheers,
George





Message #4 by "Randy Cornish" <rlcornish@c...> on Mon, 3 Jun 2002 01:08:45
If you have an Access2000 GUI talking to tables across the world, you may 
want to get creative.  Can you cache static data on the user's machine 
(data that doesn't change very often)?  You could create a "freshness 
date" on the central table, and if your user has an older date, they must 
first wait for static data to get refreshed.

Then, you need to make sure your indexes are PERFECT.  Any time you query 
one of your tables with criteria, make sure there is an index on that 
field.  Use small key fields (like Long data types).  Make sure your 
SELECT statements do not get any more fields than you absolutely need.

If you get creative, you can even process your updates asynchronously 
with some sort of semaphore.  Perhaps the user's ID is inserted in one 
field on the table to indicate that he/she has a lock on it and others 
can only access in read-only until the user is finished.  This sort 
of "home-grown" locking model might help.

Access replication is something I am not too familiar with and try to 
avoid.

if you can, try to have your Access2000 interfaces talk to MSDE or SQL 
Server at the central office.  At the very least, separate your data 
access code so that you can change from an Access backend to a SQL 
backend without changing much code.

Finally, baud rate is similar to BPS transfer rate.  A DSL line, commonly 
384,000 BPS would be roughly 400K baud.  Older computers in the 70s 
typically transferred data over phone lines at 300 baud (1000 times 
slower) and then eventually worked up to 2400 baud (a screamer in those 
days).  New technologies have blown away those earlier limits.  I was 
taught (before the days of browser interfaces with all those graphcis) to 
try and code all data transfer as though you were using a 2400 baud 
line.  This means you need to think EVERYTHING through very carefully.  
These days, this is probably overkill and would slow development down and 
inconvenience all users EXCEPT those dialing in from remote places in the 
world.


R

> Randy,
Thanks for your reply, here's the answers of your doubt:
1. Interface= Access2000
2. Yes, each laptop has the interface.
3. Around 20-30 thousand records (4 Tables)

What is baud rate by the way?


Cheers,
George


-----Original Message-----
From: Randy Cornish [mailto:rlcornish@c...]
Sent: Sunday, June 02, 2002 12:39 AM
To: Access
Subject: [access] Re: Back-End on the Web Server


Not enough information to make a quality suggestion.  When you 
say "Interface", is that a VB app, an Access MDB or a browser interface?  
Another way to ask that is: Will the user will have the application 
installed on their laptop?

How much data transfer is involved?

Is Microsoft WTS (Windows Terminal Server) an option?

What baud rate can be assumed?  (It is probably best to design as if the 
user had to work over a 2400 baud line, especially for International 
situations.

Is using SQL Server 2000 and its support for XML an option?


R

> 
Hi Guys,

Just a thought!

I have a prospective project which required to access the database 
wherever country the user is.

The scenario is, 5 user's has it's own Laptop and used to travel around 
the world except for the Master Data Entry Operator using
normal pc at the base.

The main objective is, wherever country the 5 user is, they can access 
the database anytime by establishing the connection to the
Back-End Server and open the Interface on their laptop and access all the 
features of the application. Furthermore, who ever do some
updates, the changes must reflect same as you are in the local area 
network.

Is Access can achieved the above requirements? Any idea is welcome and 
highly appreciated.


Cheers,
George



Message #5 by "George Oro" <george@c...> on Mon, 3 Jun 2002 08:31:45 +0400
Randy,

I guess this is a big challenge or I rather drop it.

Many, many thanks for you tips...


cheers,
George





-----Original Message-----
From: Randy Cornish [mailto:rlcornish@c...]
Sent: Monday, June 03, 2002 1:09 AM
To: Access
Subject: [access] Re: Back-End on the Web Server


If you have an Access2000 GUI talking to tables across the world, you may 
want to get creative.  Can you cache static data on the user's machine 
(data that doesn't change very often)?  You could create a "freshness 
date" on the central table, and if your user has an older date, they must 
first wait for static data to get refreshed.

Then, you need to make sure your indexes are PERFECT.  Any time you query 
one of your tables with criteria, make sure there is an index on that 
field.  Use small key fields (like Long data types).  Make sure your 
SELECT statements do not get any more fields than you absolutely need.

If you get creative, you can even process your updates asynchronously 
with some sort of semaphore.  Perhaps the user's ID is inserted in one 
field on the table to indicate that he/she has a lock on it and others 
can only access in read-only until the user is finished.  This sort 
of "home-grown" locking model might help.

Access replication is something I am not too familiar with and try to 
avoid.

if you can, try to have your Access2000 interfaces talk to MSDE or SQL 
Server at the central office.  At the very least, separate your data 
access code so that you can change from an Access backend to a SQL 
backend without changing much code.

Finally, baud rate is similar to BPS transfer rate.  A DSL line, commonly 
384,000 BPS would be roughly 400K baud.  Older computers in the 70s 
typically transferred data over phone lines at 300 baud (1000 times 
slower) and then eventually worked up to 2400 baud (a screamer in those 
days).  New technologies have blown away those earlier limits.  I was 
taught (before the days of browser interfaces with all those graphcis) to 
try and code all data transfer as though you were using a 2400 baud 
line.  This means you need to think EVERYTHING through very carefully.  
These days, this is probably overkill and would slow development down and 
inconvenience all users EXCEPT those dialing in from remote places in the 
world.


R

> Randy,
Thanks for your reply, here's the answers of your doubt:
1. Interface= Access2000
2. Yes, each laptop has the interface.
3. Around 20-30 thousand records (4 Tables)

What is baud rate by the way?


Cheers,
George


-----Original Message-----
From: Randy Cornish [mailto:rlcornish@c...]
Sent: Sunday, June 02, 2002 12:39 AM
To: Access
Subject: [access] Re: Back-End on the Web Server


Not enough information to make a quality suggestion.  When you 
say "Interface", is that a VB app, an Access MDB or a browser interface?  
Another way to ask that is: Will the user will have the application 
installed on their laptop?

How much data transfer is involved?

Is Microsoft WTS (Windows Terminal Server) an option?

What baud rate can be assumed?  (It is probably best to design as if the 
user had to work over a 2400 baud line, especially for International 
situations.

Is using SQL Server 2000 and its support for XML an option?


R

> 
Hi Guys,

Just a thought!

I have a prospective project which required to access the database 
wherever country the user is.

The scenario is, 5 user's has it's own Laptop and used to travel around 
the world except for the Master Data Entry Operator using
normal pc at the base.

The main objective is, wherever country the 5 user is, they can access 
the database anytime by establishing the connection to the
Back-End Server and open the Interface on their laptop and access all the 
features of the application. Furthermore, who ever do some
updates, the changes must reflect same as you are in the local area 
network.

Is Access can achieved the above requirements? Any idea is welcome and 
highly appreciated.


Cheers,
George





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