[Info-vax] VMS Software: New US Mailing Address

[Richard Maher]

On 14/10/2022 7:14 am, Arne Vajhøj wrote:
> On 10/13/2022 6:25 PM, Bill Gunshannon wrote:
>> On 10/13/22 17:40, Jan-Erik Söderholm wrote:
>>> Think of it as a compiler for a language called "SQL". The
>>> default file type for these files (on VMS) is .SQLMOD
>>> 
>>> It's more or less "just" as a compiler for any other language. 
>>> And it creates a object files that are no different from any 
>>> other object file, may it come from C, Pascal or whatever.
>>> 
>>> That object file can then be linked into any other application 
>>> following the VMS calling standard. That other language does not 
>>> need to have any native support for Rdb, it just has to follow
>>> the VMS calling standard.
>>> 
>>> It is just a function call with some parameters that returns
>>> some defined result. The caller does not need to know that it was
>>> Rdb that returned the result.
>> 
>> Well, that's pretty cool.  I have never seen COBOL used that way 
>> although there really is no reason not to.  Just like the
>> libraries linked to from the EXEC SQL parts of the code are
>> actually C or C++ snippets.  You can directly link to the PostGres
>> Libraries but, for obvious reasons, using the Embedded SQL method
>> is easier on the programmer.
> 
> Embedded SQL is pretty efficient - few lines achieve much - way more
> efficient than library calls in compiled languages (probably less
> efficient than library calls in scripts languages and ORM).
> 
> But the industry is moving away from embedded SQL and precompilers.
> 
> Oracle DB - only supports C and Cobol - it has dropped Fortran
> 
> MySQL/MariaDB - no pre-compilers
> 
> PostgreSQL - only C (from project itself - an open source Cobol
> exist)
> 
> SQLServer - dropped all support
> 
> DB2 - still support Cobol, PL/I and C (maybe also Fortran - not
> sure)
> 
> Sybase (or whatever SAP calls it today) - I believe they have dropped
>  all support
> 
> SQLite - no pre-compilers
> 
> NoSQL databases (MongoDB etc.) - obviously no embedded SQL  :-)
> 
> Arne
> 
> 
> 
> 
> 

  IIRC Oracle/Rdb is the only RDBMS that executes in the context of the 
calling process through DSRI. Sounds pretty efficient. Dynamic qyuery 
optimization notwithstanding.