Tying tables together in MySql

I have one table that includes company information (i.e. name, address, business description...) and another table that has user information (i.e. first name, last name, email and password). How do I tie the company table to the user table so that when the user logs in, the company is properly associated with the user? Would I have a userid column in the company table?

From stackoverflow

• You are looking for joins.

  Companies would have a one-to-many relationship with the users, so you need to create a column in the user table with a name like company_id and then query it like this to get users and their company:

  SELECT * FROM users INNER JOIN companies ON users.company_id = companies.id
  

  Paolo Bergantino : :? How is this wrong? I'm rereading the question and this is what he's asking about.

  BrynJ : Agree, I'm not sure why your answer would be down-voted

  Adrien : +1 From me ... Also, see http://stackoverflow.com/questions/832322/question-about-joining-two-mysql-tables/

• Assuming that several users might belong to a single company but only one company may be associated with a user, a companyid in the user table would make the most sense.

  To join two tables together where you expect a match between both in all cases, use an INNER JOIN:

  SELECT u.*, c.companyname FROM users u 
  INNER JOIN companies c ON u.companyid = c.companyid
  

  Obviously, the above is a simulated query and needs tailoring to match your schema / requirements.

• No, you will probably have a one-to-many relation. So one company contains many employees. But one employee belongs to only one company (to keep things simple).

  This requires a foreign key in the user table pointing to the id of the company.