Re: Imperative Query Languages

[John Turner <fenwayriffs@xxxxxxxxx>]

(copying the list)

On Wed, Jul 5, 2017 at 12:22 AM, Jason Dusek <jason.dusek@xxxxxxxxx> wrote:

Are there any “semi-imperative” query languages that have been tried in the past? 

not particularly relevant to the Unix or Windows worlds, but on OpenVMS there's Datatrieve:

https://en.wikipedia.org/wiki/DATATRIEVE

-John

On Wed, Jul 5, 2017 at 12:22 AM, Jason Dusek <jason.dusek@xxxxxxxxx> wrote:

Hi All,

This more of a general interest than specifically Postgres question. Are there any “semi-imperative” query languages that have been tried in the past? I’m imagining a language where something like this:

for employee in employees:
    for department in department:
        if employee.department == department.department and
           department.name == "infosec":
            yield employee.employee, employee.name, employee.location, employee.favorite_drink

would be planned and executed like this:

SELECT employee.employee, employee.name, employee.location, employee.favorite_drink
  FROM employee JOIN department USING (department)
 WHERE department.name == "infosec"

The only language I can think of that is vaguely like this is Fortress, in that it attempts to emulate pseudocode and Fortran very closely while being fundamentally a dataflow language.

Kind Regards,

  Jason

​