It makes sense that as foreign keys can be composite, that all foreign keys would be considered composite, thank you, I just had no idea that foreign keys could be composite in the same way that primary keys could be. Thanks again
On Fri, Jan 1, 2021 at 8:29 AM Mike Bayer <mike...@zzzcomputing.com> wrote: > A particular column may be constrained by more than one foreign key > constraint (although this is very uncommon), and a particular foreign key > constraint may be "composite" in that it refers to multiple columns. All > primary and foreign key constructs in SQLAlchemy are inherently > composite. having APIs that refer to single-column keys, like > "table.primary_key_column" and stuff like that, encourages applications to > hardcode themselves to be non-composite, and there's really no point in > doing so. If I'm writing a program that looks at primary and foreign key > constraints in an abstract sense I would want it to assume composite in all > cases. > > > > On Thu, Dec 31, 2020, at 3:53 PM, Matthew Graham wrote: > > Are you saying with the multiple foreign keys that for each key, multiple > columns can be used? I am aware that if you had table A and it had columns > B_id and C_id that B_id may be a fk to B and C_id may be a reign key to C, > but are you essentially saying there is an equivalence to a "composite" > foreign key so that you can have a foreign key on columns B_id1 and B_id2 > in A to refer to, only in conjunction, B? > Also thanks for referring me to inspector, I will give that a go > > > -- > SQLAlchemy - > The Python SQL Toolkit and Object Relational Mapper > > http://www.sqlalchemy.org/ > > To post example code, please provide an MCVE: Minimal, Complete, and > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > description. > --- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sqlalchemy+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sqlalchemy/CAP-Gp5PoX7vvcfOUN2j3RS1LM8Cv300YmT7Ne3e1YzXc3J3Gkg%40mail.gmail.com > <https://groups.google.com/d/msgid/sqlalchemy/CAP-Gp5PoX7vvcfOUN2j3RS1LM8Cv300YmT7Ne3e1YzXc3J3Gkg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > > -- > SQLAlchemy - > The Python SQL Toolkit and Object Relational Mapper > > http://www.sqlalchemy.org/ > > To post example code, please provide an MCVE: Minimal, Complete, and > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > description. > --- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sqlalchemy+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sqlalchemy/12781196-61f2-4ac7-9df3-762982e5cac4%40www.fastmail.com > <https://groups.google.com/d/msgid/sqlalchemy/12781196-61f2-4ac7-9df3-762982e5cac4%40www.fastmail.com?utm_medium=email&utm_source=footer> > . > -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/CAP-Gp5OEMB50h%3DSeOY-jTg5BGp0_7hvhEd8dGzWBbOX6TUHQrA%40mail.gmail.com.
