SQL2GMS - GAMS

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SQL2GMS
We can also let SQL2GMS create the GDX file:
MDB2GDX2.GMS:
$ontext
Store data from Access database into a GDX file.
$offtext
$onecho > cmd.txt
C=Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%system.fp%transportation.mdb
X=%system.fp%transportation.gdx
Q1=select name from suppliers
S1=i
Q2=select name from demandcenters
S2=j
Q3=select name,demand from demandcenters
A3=demand
Q4=select name,supply from suppliers
A4=supply
Q5=select supplier,demandcenter,distance from distances
A5=dist
$offecho
$call =sql2gms.exe @cmd.txt
The first approach has the advantage that a complete audit record is available from the data moved from
the database to the GDX file in the sr0.lst listing file. If someone ever wonders what came out of the
database and how this was stored in the GDX file, that file gives the answer.
To load the GDX data the following fragment can be used:
GDXTRNSPORT.GMS:
$ontext
Load transportation data from GDX file
Compile time loading
$offtext
set i 'suppliers';
set j 'demand centers';
parameter demand(j);
parameter supply(i);
parameter dist(i,j) 'distances';
$gdxin transportation.gdx
$load i j demand supply dist
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