Re: join on

[Jonathon Coombes]

Looking at your syntax:

SELECT * FROM Dammreg INNER JOIN Dammreg ON Dammreg.DNAMN LIKE CONCAT('%', Damm_vk.NAMN, '%');

and received the error message: #1066 - Not unique table/alias: 'Dammreg'.

The reason for this is that you are joining the table to itself, but don't specify aliases to distinguish different fields of the same names. Also, using a function within the join condition is bad. Instead try the following syntax:

SELECT *
FROM Dammreg AS d1
INNER JOIN Dammreg AS d2 ON (d1.DNAMN=d2.DNAMN)
WHERE d1.DNAMN LIKE '%Damm_vk.NAMN%');

Further details on table aliases are in the manual at:

http://dev.mysql.com/doc/refman/5.5/en/join.html