How to get the foreignkey details of a foreignkey in a table in flask sqlalchemy?










-1















I have 3 tables like table1,table2 and table3,here table 2 is child of table 1 and table 3 is child of table2, when i query on table3 i want to get the foreignkey details table2 and table1.










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  • What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

    – Tobin
    Nov 14 '18 at 9:20











  • I don't know how to do that so posted a question.

    – ganesh s
    Nov 14 '18 at 10:01















-1















I have 3 tables like table1,table2 and table3,here table 2 is child of table 1 and table 3 is child of table2, when i query on table3 i want to get the foreignkey details table2 and table1.










share|improve this question
























  • What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

    – Tobin
    Nov 14 '18 at 9:20











  • I don't know how to do that so posted a question.

    – ganesh s
    Nov 14 '18 at 10:01













-1












-1








-1








I have 3 tables like table1,table2 and table3,here table 2 is child of table 1 and table 3 is child of table2, when i query on table3 i want to get the foreignkey details table2 and table1.










share|improve this question
















I have 3 tables like table1,table2 and table3,here table 2 is child of table 1 and table 3 is child of table2, when i query on table3 i want to get the foreignkey details table2 and table1.







python-3.x flask flask-sqlalchemy flask-restful






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edited Nov 15 '18 at 11:45







ganesh s

















asked Nov 14 '18 at 4:40









ganesh sganesh s

16




16












  • What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

    – Tobin
    Nov 14 '18 at 9:20











  • I don't know how to do that so posted a question.

    – ganesh s
    Nov 14 '18 at 10:01

















  • What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

    – Tobin
    Nov 14 '18 at 9:20











  • I don't know how to do that so posted a question.

    – ganesh s
    Nov 14 '18 at 10:01
















What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

– Tobin
Nov 14 '18 at 9:20





What have you tried? Have you read the official sqlalchemy documentation? It's easier to help you if your problem is more precise and if at least there is a code that you tried!

– Tobin
Nov 14 '18 at 9:20













I don't know how to do that so posted a question.

– ganesh s
Nov 14 '18 at 10:01





I don't know how to do that so posted a question.

– ganesh s
Nov 14 '18 at 10:01












1 Answer
1






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oldest

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0














There is an excellent tutorial on databases with Flask-sqlAlchemy here.



The simplest idea, if I understood your question correctly, is to make a two-part request. First you find a specific info in table1, then you link it to the second query to find information in table2 or eventually table3.



Concretely, suppose it is a blog. You have two tables: your table1 contains all the users (table1=Users) and the table2 contains the publications of the users (table2=Posts). There is a foreign key that links the two tables. Now you would like to see all posts for user 'John'. What you do is start by finding the user John, then you look for all the posts related to him:



>>> user = Users.query.filter_by(username='John').first()
>>> posts = user.Posts.all()





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    1 Answer
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    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    0














    There is an excellent tutorial on databases with Flask-sqlAlchemy here.



    The simplest idea, if I understood your question correctly, is to make a two-part request. First you find a specific info in table1, then you link it to the second query to find information in table2 or eventually table3.



    Concretely, suppose it is a blog. You have two tables: your table1 contains all the users (table1=Users) and the table2 contains the publications of the users (table2=Posts). There is a foreign key that links the two tables. Now you would like to see all posts for user 'John'. What you do is start by finding the user John, then you look for all the posts related to him:



    >>> user = Users.query.filter_by(username='John').first()
    >>> posts = user.Posts.all()





    share|improve this answer



























      0














      There is an excellent tutorial on databases with Flask-sqlAlchemy here.



      The simplest idea, if I understood your question correctly, is to make a two-part request. First you find a specific info in table1, then you link it to the second query to find information in table2 or eventually table3.



      Concretely, suppose it is a blog. You have two tables: your table1 contains all the users (table1=Users) and the table2 contains the publications of the users (table2=Posts). There is a foreign key that links the two tables. Now you would like to see all posts for user 'John'. What you do is start by finding the user John, then you look for all the posts related to him:



      >>> user = Users.query.filter_by(username='John').first()
      >>> posts = user.Posts.all()





      share|improve this answer

























        0












        0








        0







        There is an excellent tutorial on databases with Flask-sqlAlchemy here.



        The simplest idea, if I understood your question correctly, is to make a two-part request. First you find a specific info in table1, then you link it to the second query to find information in table2 or eventually table3.



        Concretely, suppose it is a blog. You have two tables: your table1 contains all the users (table1=Users) and the table2 contains the publications of the users (table2=Posts). There is a foreign key that links the two tables. Now you would like to see all posts for user 'John'. What you do is start by finding the user John, then you look for all the posts related to him:



        >>> user = Users.query.filter_by(username='John').first()
        >>> posts = user.Posts.all()





        share|improve this answer













        There is an excellent tutorial on databases with Flask-sqlAlchemy here.



        The simplest idea, if I understood your question correctly, is to make a two-part request. First you find a specific info in table1, then you link it to the second query to find information in table2 or eventually table3.



        Concretely, suppose it is a blog. You have two tables: your table1 contains all the users (table1=Users) and the table2 contains the publications of the users (table2=Posts). There is a foreign key that links the two tables. Now you would like to see all posts for user 'John'. What you do is start by finding the user John, then you look for all the posts related to him:



        >>> user = Users.query.filter_by(username='John').first()
        >>> posts = user.Posts.all()






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        share|improve this answer










        answered Nov 14 '18 at 14:27









        TobinTobin

        31118




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