[AccessD] Design Pointers - Mapping Routes

[David Emerson]

Thanks Jim and Stuart, that will get me started.  Our preference is to keep
all the calculations within Access/SQL as this is a commercial application
and users may not necessarily have Excel.

Regards

David Emerson
Dalyn Software Ltd
Wellington, New Zealand



-----Original Message-----
From: AccessD <accessd-bounces+newsgrps=dalyn.co.nz at databaseadvisors.com> On
Behalf Of James Button via AccessD
Sent: Thursday, 4 November 2021 10:36 am
To: 'Access Developers discussion and problem solving'
<accessd at databaseadvisors.com>
Cc: James Button <jamesbutton at blueyonder.co.uk>
Subject: Re: [AccessD] Design Pointers - Mapping Routes

Also - see
<https://techcommunity.microsoft.com/t5/excel-blog/preview-of-stocks-and-geo
grap
hy-new-data-types-in-excel/ba-p/176185>
That is a link from within
<https://techcommunity.microsoft.com/t5/excel-blog/announcing-data-types-api
s-da
ta-types-in-excel-add-ins/ba-p/2901516>

Maybe not exactly relevant to your request, but looks, at first glance) as
if Excel is being enhanced to more easily manipulate compound data entries
So - maybe Access FE for data input, storage, access control and selection
of data to be reported on Excel for doing the reporting Maybe even Excel.com
with officescript  to handle data specification from an Excel interface,
validate the requester is appropriately authorised check expected data
volume, and then request the  data,  finally reporting on it as required.

JimB 

-----Original Message-----
From: AccessD
<accessd-bounces+jamesbutton=blueyonder.co.uk at databaseadvisors.com> On
Behalf Of Stuart McLachlan
Sent: Wednesday, November 3, 2021 8:54 PM
To: Access Developers discussion and problem solving
<accessd at databaseadvisors.com>
Subject: Re: [AccessD] Design Pointers - Mapping Routes

"Graph Theory"
https://en.wikipedia.org/wiki/Graph_theory

:)

--
Stuart

On 4 Nov 2021 at 9:22, David Emerson wrote:

> Hi Listers,
> 
> A table storing travel routes has fields for two points.  Data might 
> look like this:
> 
> Point 1		Point 2
> A		B
> A		C
> B		C
> B		D
> C		D
> C		E
> E		D
> 
> As can be seen from the last record, the order of the point data may 
> not be lowest/highest (it would be easier if the record could be 
> entered as D/E but this is not the case).  There will however only be 
> one combination of points (eg since there is a record for E/D there 
> cannot be a record entered for D/E).
> 
> Questions to be answered from the data could be:
> 1) What are the possible routes from A to C (without covering the same 
> section twice)? Answers: A-B, B-C A-C
> 
> 2) What are the possible routes from A to D (without covering the same 
> section twice)? Answers: A-B, B-C, C-D A-B, B-C, C-E, E-D A-B, B-D
> 
> 3) What are the possible routes from A to E (without covering the same 
> section twice)? Answers: A-B, B-C, C-D, D-E (note that D-E is the E/D
> record) A-B, B-C, C-E A-B, B-D, D-E (note that D-E is the E/D record) 
> A-C, C-D, D-E (note that D-E is the E/D record) A-C, C-E
> 
> To get the answers it seems that I will need to use queries to come up 
> with the different permutations for each record (eg E/D and D/E) so I 
> can get all the matches of end point to start point values (and I 
> would also need to check that the same route isn't used more than
> once)
> 
> Is there a better table structure to achieve this?
> 
> Can anyone point me in the right direction as to any theory behind 
> this type of mapping, and any code that might help generate the 
> solutions?
> 
> Regards
> 
> David Emerson
> Dalyn Software Ltd
> Wellington, New Zealand
> 
> 
> 
> 
> 
> --
> AccessD mailing list
> AccessD at databaseadvisors.com
> https://databaseadvisors.com/mailman/listinfo/accessd
> Website: http://www.databaseadvisors.com
> 


-- 
AccessD mailing list
AccessD at databaseadvisors.com
https://databaseadvisors.com/mailman/listinfo/accessd
Website: http://www.databaseadvisors.com

-- 
AccessD mailing list
AccessD at databaseadvisors.com
https://databaseadvisors.com/mailman/listinfo/accessd
Website: http://www.databaseadvisors.com

-- 
AccessD mailing list
AccessD at databaseadvisors.com
https://databaseadvisors.com/mailman/listinfo/accessd
Website: http://www.databaseadvisors.com