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EJB QL syntax  RSS feed

 
Ramakrishnan Ponmudi
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All the follwing ejb-ql statements are correct or not?

SELECT OBJECT(c) FROM customer c, IN(o.order) o
SELECT OBJECT(c) FROM customer AS c, IN(o.order) o
SELECT OBJECT(c) FROM customer AS c, IN(o.order) AS o
SELECT OBJECT(c) FROM customer c IN(o.order) o
(note: In the fourth query "," is removed)
 
Muthaiah Ramanathan
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I would believe all of them are correct... EJB Geeks, correct me if I am wrong.
 
Saeed Amer
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Though I am not EJB or EJB-QL expert but to me all of the four queries seem be wrong. Where is this "o" declared/defined in the query? "c" is placeholder/alias for "customer". What does "o" represent?

SELECT OBJECT(c) FROM customer c, IN(o.order) o
SELECT OBJECT(c) FROM customer AS c, IN(o.order) o
SELECT OBJECT(c) FROM customer AS c, IN(o.order) AS o
SELECT OBJECT(c) FROM customer c IN(o.order) o

 
Ankit Doshi
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I think the queries are incorrect. I think, the query to "select the customers who have at least one order" should look like this:

SELECT OBJECT(c) FROM Customer c, IN(c.order) o

For the four queries below, I think you are trying to write the same query in four different ways. Not sure about the third and the fourth syntax.
 
It is sorta covered in the JavaRanch Style Guide.
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