One table which references many other id's
I know this must be a super beginner question, but how do I create a table which has a column which can reference multiple id's of other tables? i.e.: One user may have many communities, and a community belongs开发者_Python百科 to several different users. Is this possible? Does the question make sense?
[edit]Is this -> Many-to-many relationship INSERT the only way?
Normally you won't have a column in one that references multiple IDs. You'll normally setup a third table to hold that information. Let me give an example:
Say you have a table for "Pages" on a web-site
"Pages Table"
Page_ID | Page_Name
1 Home
Say you want to include some articles on those pages that are stored in another table
"Articles Table"
Article_ID | Article_Text
1 SQL is Fun!
2 Java is no fun!
And you want to be able to include a few different articles on your page, you'd make a third table, let's call it "ArticlesInPages" with the follow columns:
"ArticlesInPages Table"
Page_ID | Article_ID
1 1
1 2
You could now write SQL "SELECT * from ArticlesInPages join articles on articles.article_id = ArticlesInPages.article_id where page_id = 1"
And it would return
Page_ID | Article_ID | Article_Text
1 1 SQL Is Fun!
1 2 Javs is No Fun!
This would return both the articles, hope this helps!
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