The Query that i am using is :
SELECT a.col1,b.col1,c.col1 FROM Cylinder a LEFT JOIN Valve b ON a.ColumnNum=b.ColumnNum LEFT JOIN Regulater c ON a.ColumnNum=c.ColumnNum


But it gives me following error
outer or full join must be followed by path expression

Is there any problem in the format that i am using?
I am not able to find what the actual problem is.

Can anyone help me in this regards.
Thanks in advance