Select statement to join tables?

For a simple join:

SELECT a.*, b.*
FROM tblAlpha a, tblBeta b
WHERE (a.keyfield = b.foreignkey);

It's often smarter to do an outer join, especially if you need rows in tblAlpha to show up in your resultset even if there is no matching record in tblBeta:

SELECT a.*, b.*
FROM tblAlpha a LEFT OUTER JOIN tblBeta b ON a.keyfield = b.foreignkey;

If you want to get into the nuts and bolts of it, the MySQL doc is found at:
http://www.mysql.com/doc/en/JOIN.html

Hjälpte svaret dig?

 Skriv ut denna artikeln

Läs även

How do I delete a table from a database?

Use this SQL command : "DROP TABLE yourtablename"

How can I select random rows from a table?

SELECT * FROM table_name ORDER BY RAND(); Found at...

What does this error message means - Warning: Supplied argument is not a valid MySQL result resource and how do you solve it?

I think you got this message from PHP. You get this message when you are trying to access...

Does mysql support foreign keys?

The answer to this is two-fold. Yes. MySQL _DOES_ allow the creation of foreign key...

Do you provide phpMyAdmin web interface to manage the MySQL Database?

Yes, we provide that. You can login to DotNetPanel first Create MySQL Database, create MySQL...