Enhancing PGSQL to be compatible with Informix SQL

I am currently looking into the possibility of extending the current
postgres SQL implementation to be compatible with Informix's SQL
implementation.

The changes required seem relatively straightforward, with one notable
exception.

Requirements:1/    Datetime type specifiers (should have no impact)    o    informix uses datetime specifiers of the
form       DATETIME YEAR TO HOUR.  (which is just the year,        month, day and hour portion of a datetime).2/
Intervaltype specifiers (ditto)    o    informix uses interval specifiers of the form        INTERVAL DAY TO HOUR.
(whichis just the         day and hour portion of an interval).3/    Money type specifiers    o    informix has money
typespecifiers that are akin        to decimal speicifiers4/    Informix outer join syntax    o    informix uses outer
joinsof the form        SELECT * FROM a, outer b where a.nr = b.nr        This will require some post-processing to
determine       the actual join conditions.5/    serial data type    o    Serial type must return inserted key value
o   Unfortunately (and this is the big bad hit)        informix's serial datatype does serial number        generation
ona zero inserted valued.        The modification required to do this may have        impact on existing programs.
 


I'd be interested if anyone can see any conceptual difficulties i've
missed in these definitions, and welcome any concepts on the
implementation.


.............................Rod

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| Rod Chamberlin              |  rod@querix.com   Tel +44 1703 232345         |
| Software Engineer           |                   Mob +44 7803 295406         |
| QueriX                      |                   Fax +44 1703 399685         |
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