Re: How do I alter an existing column and add a foreign key whichis a Primary key to a table?

On Sunday, July 21, 2019, 10:55:13 PM GMT+8, David G. Johnston <david.g.johnston@gmail.com> wrote:


On Sunday, July 21, 2019, Karen Goh <karenworld@yahoo.com> wrote:

You can't Select s_tutor.zip_code from subject_tutor as zip_code belongs to s_tutor table.

Hence, I wrote my last message about my confusion.



You need to show your entire schema and the queries that are giving you trouble if you want to get help that is less confusing. Though as I wrote before I think your immediate problem is that you don’t have a “tutor” table on which to create the PK.

Is there a way for me to generate an entity table diagram vis pgAdmin4 or PSQL ?

David J.