Usando SQL no Magik

At the Smallworld Users Conference yesterday, I heard someone ask when GE would provide an interface to write SQL from Magik against VMDS tables. It turns out that the functionality already exists. Here are some examples.

1. You can get a SQL prompt directly at the Magik prompt...

MagikSF> sql(gis_program_manager.cached_dataset(:gis))
$
SQL> SELECT name, address1 FROM hotel ORDER BY address1
$
Name                Address 1         

Acorn Guest House   154 Chesterton Road
Hamilton Lodge      156 Chesterton Road
De Freville House   166 Chesterton Road
Rosswill            17 Chesterton Road
Cam Guest House     17 Elizabeth Way  
Kirkwood House      172 Chesterton Road
All Seasons         219 Chesterton Road
Lyngamore           35 Chesterton Road
Suffolk House       69 Milton Road    
Southampton House   7 Elizabeth Way   
Ashley Hotel        74 Chesterton Road
Arundel House       Chesterton Road   
Gonville Hotel      Gonville Place    
Garden House        Granta Place      
University Arms     Regent Street     

15 record(s) selected
SQL> SQL> select count(*) from min_road
$
COUNT(*)

833     

1 record(s) selected
SQL> SQL>

NOTE: the sql() procedure is defined in module :sql2. You can load that module if your image doesn't have the sql() procedure loaded.

2. You can also use the sql2_parser object directly in your Magik code.
You can find out more by searching the Smallworld documentation for "SQL Support". To be clear, this is not the same as Smallworld's SQL Server image code. This is strictly related to writing SQL in Magik to query Smallworld tables.

I have never used this in code, but I suppose it could come in handy if you were more comfortable writing a SQL statement compared to writing a selection predicate. I'm curious to hear if anyone else uses this SQL functionality within Smallworld.