[Help-glpk] SQL Support for GLPK: Which syntax is needed?

[glpk xypron]

As described before I started to implement SQL support for GLPK-4.23.
Syntax description: ftp://glpk.dyndns.org/glpk/gmpl-sql.20071103.pdf
Implementation (Linux only up to now): 
ftp://glpk.dyndns.org/glpk/glpk-4.23-sql-20071103.tar.gz

Andrew asked if the "table" statements of AMPL would be a better choice for the 
syntax.
The table statements of AMPL are described in:
http://www.gams.com/presentations/present_AMPL.pdf
http://www.ampl.com/NEW/tables.html
http://www.netlib.org/ampl/tables/TABLES.RME

An approach different to AMPL can be found in ILOG OPL:
http://www.iitb.ac.in/~ieor/resources/opl40/usropllangref/index.html
(see chapter "Database Initialization")

What do the AMPL and the ILOG approach have in common:
Definitions of database connectivity is separated from the model.
- AMPL puts the database statement into the run file (which defines the data 
and model files to be used).
- ILOG OPL puts all database statements into the data file.

What are the main differences:
In the ILOG syntax SQL commands have to be specified. This requires some 
knowledge of SQL by the user. The full wealth of SQL can be used.

The AMPL syntax needs no SQL knowledge at all. The table commands are very 
powerful: they can drop and create new database tables, and they can update the 
structure of existing database tables. 

In AMPL SQL can only be specified for reading tables. Testing with the students 
edition showed the following limitations: The IN mode of table access cannot 
add records. The INOUT and the OUT mode of table access cannot be stopped from 
changing the table structure: keys definitions lost, new columns added, columns 
width adjusted.

Which direction should GLPK database connectivity syntax head?
- Should it be focused on the modeling part like the AMPL table statements. No 
SQL knowledge needed at all. 
- Should it offer access full access to SQL?

I would be happy hear, what is important to the other members of the GLPK 
community.

Best regards 

Xypron
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