Is it possible to use multiple databases within same query using pg-promise?












2















I have two related tables T1 and T2 in different databases D1 and D2. I need to do an inner join between two tables.



From here: Joining Results from Two Separate Databases it is clear that separate queries should be made to two databases and results to be consolidated on client side OR use dblink / postgres-fdw.



However, I see this issue: Multiple Databases #1
and the use of $dc parameter here: pg-promise/Database.



I believe issue: Multiple Databases #1
just facilitates allowing connecting to multiple databases within the same codebase.



The description of $dc parameter states:




This is mainly to facilitate the use of multiple databases which may need separate protocol extensions, or different implementations within a single task




However, I did not find any examples.



Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?



Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?










share|improve this question



























    2















    I have two related tables T1 and T2 in different databases D1 and D2. I need to do an inner join between two tables.



    From here: Joining Results from Two Separate Databases it is clear that separate queries should be made to two databases and results to be consolidated on client side OR use dblink / postgres-fdw.



    However, I see this issue: Multiple Databases #1
    and the use of $dc parameter here: pg-promise/Database.



    I believe issue: Multiple Databases #1
    just facilitates allowing connecting to multiple databases within the same codebase.



    The description of $dc parameter states:




    This is mainly to facilitate the use of multiple databases which may need separate protocol extensions, or different implementations within a single task




    However, I did not find any examples.



    Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?



    Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?










    share|improve this question

























      2












      2








      2








      I have two related tables T1 and T2 in different databases D1 and D2. I need to do an inner join between two tables.



      From here: Joining Results from Two Separate Databases it is clear that separate queries should be made to two databases and results to be consolidated on client side OR use dblink / postgres-fdw.



      However, I see this issue: Multiple Databases #1
      and the use of $dc parameter here: pg-promise/Database.



      I believe issue: Multiple Databases #1
      just facilitates allowing connecting to multiple databases within the same codebase.



      The description of $dc parameter states:




      This is mainly to facilitate the use of multiple databases which may need separate protocol extensions, or different implementations within a single task




      However, I did not find any examples.



      Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?



      Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?










      share|improve this question














      I have two related tables T1 and T2 in different databases D1 and D2. I need to do an inner join between two tables.



      From here: Joining Results from Two Separate Databases it is clear that separate queries should be made to two databases and results to be consolidated on client side OR use dblink / postgres-fdw.



      However, I see this issue: Multiple Databases #1
      and the use of $dc parameter here: pg-promise/Database.



      I believe issue: Multiple Databases #1
      just facilitates allowing connecting to multiple databases within the same codebase.



      The description of $dc parameter states:




      This is mainly to facilitate the use of multiple databases which may need separate protocol extensions, or different implementations within a single task




      However, I did not find any examples.



      Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?



      Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?







      node.js postgresql pg-promise






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 24 '18 at 8:48









      Naisheel VerdhanNaisheel Verdhan

      2,5361127




      2,5361127
























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          Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?




          It is the former.




          Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?




          No. Each Database object represents only a single connection to A database.



          Database Context is there to allow re-use of tasks, transactions and protocol extensions across multiple Database objects, by relying on its value.






          share|improve this answer

























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            1 Answer
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            active

            oldest

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            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            2















            Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?




            It is the former.




            Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?




            No. Each Database object represents only a single connection to A database.



            Database Context is there to allow re-use of tasks, transactions and protocol extensions across multiple Database objects, by relying on its value.






            share|improve this answer






























              2















              Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?




              It is the former.




              Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?




              No. Each Database object represents only a single connection to A database.



              Database Context is there to allow re-use of tasks, transactions and protocol extensions across multiple Database objects, by relying on its value.






              share|improve this answer




























                2












                2








                2








                Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?




                It is the former.




                Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?




                No. Each Database object represents only a single connection to A database.



                Database Context is there to allow re-use of tasks, transactions and protocol extensions across multiple Database objects, by relying on its value.






                share|improve this answer
















                Is the $dc paramter just a database context object that can be accessed, or would it allow to do an inner join between two different databases?




                It is the former.




                Is there a way to do utilise two database connections but do a join across databases in without having to do it on client-side using pg-promise?




                No. Each Database object represents only a single connection to A database.



                Database Context is there to allow re-use of tasks, transactions and protocol extensions across multiple Database objects, by relying on its value.







                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited Nov 24 '18 at 10:51

























                answered Nov 24 '18 at 9:51









                vitaly-tvitaly-t

                11.1k34771




                11.1k34771
































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