Hie,
I have 3 tables namely Accounts
, Companies
and Freelancers
. The accounts table holds the email
, password
and account_type
fields where if account_type
values is an ENUM('companies','freelancers')
. I want to know how I can write a query that Joins with Companies
Table if account_type
fields is equal to companies
else should Join with Freelancers
If you want to get all the data to one table,
you can simply use a union
to bind 2 results sets that you get from joining 2 tables.
SELECT * FROM users Accounts a LEFT JOIN Companies c ON c.account_id = a.id WHERE a.account_type = 'companies' UNION SELECT * FROM users Accounts a LEFT JOIN Freelancers f ON f.account_id = a.id WHERE a.account_type = 'freelancers'
You can join the tables according to the ids by getting the ids to one table.
SELECT Accounts.id, Accounts.type, Companies.account_id AS id2, Freelancers.account_id AS id3 FROM Accounts LEFT JOIN Companies ON Accounts.id = Companies.account_id AND Accounts.type = 'companies' LEFT JOIN Freelancers ON Freelancers.account_id = Accounts.id AND Accounts.type = 'freelancers'
I hope this will help you to resolve your issue.
For example
SELECT Accounts.column1,
COALESCE(Companies.column2, Freelancers.column3), -- common column
Companies.column4, -- specific column
Freelancers.column5 -- specific column
FROM Accounts
LEFT JOIN Companies ON Companies.account_id = Accounts.id
AND Accounts.account_type = 'companies'
LEFT JOIN Freelancers ON Freelancers.account_id = Accounts.id
AND Accounts.account_type = 'freelancers'
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