Hi Tom
It seems the context of the question was not very clear from the
mail. Sorry for that!
"empinfo.phone.empid" is actually a join attribute for
joining employee and phone tables.
Here is some sample code:
Class<?> emptype =
dcl.createDynamicClass("jpatest.empinfo");
Class<?> phonetype =
dcl.createDynamicClass("jpatest.phone");
DynamicTypeBuilder empBuilder = new
JPADynamicTypeBuilder(primaryType, null, "empinfo");
DynamicTypeBuilder phoneBuilder = new
JPADynamicTypeBuilder(secondaryType, null, "phone");
/**
... add the direct mappings here
*/
empBuilder.addOneToManyMapping("empinfo.phone.empid",
phoneBuilder.getType(), "phone.empid");
phoneBuilder.addOneToOneMapping("empinfo.phone.empid",
empBuilder.getType(), "phone.empid");
helper.addTypes(false, true, empBuilder.getType(),
phoneBuilder.getType());
ReadAllQuery query = new
DynamicHelper(session).newReadAllQuery(empBuilder.getType().getDescriptor().getAlias());
// if I reverse the order of the two, then the query is
not generated properly as explained in the mail below
query.addJoinedAttribute(query.getExpressionBuilder().anyOf("empinfo.phone.empid"));
query.setSelectionCriteria(query.getExpressionBuilder().anyOf("empinfo.phone.empid").get("phone").equal("11"));
Thanks
Hi
Rohit,
I am a bit surprised ".anyOf("empinfo.phone.empid")" works at
all. I would expect you to have to write something like:
"get("empinfo").anyOf("phone").get("empid") - i.e. When using the
_expression_ API, you should not use the "." notation within the
method calls.
-Tom
Rohit Banga wrote:
Hello All
I have a phone table and an employee table. The phone table has
a foreign key constraint on the employee id. An employee can
have multiple phones.
Now when I query for a employee having phone number say '11' I
set the selection criteria as:
query.setSelectionCriteria(
query.getExpressionBuilder().anyOf("empinfo.phone.empid").get("phone").equal("11"));
I add the following join attribute:
query.addJoinAttribute(query.getExpressionBuilder().anyOf("empinfo.phone.empid"));
_Case 1:_ If I set the selection criteria before adding the join
attribute the query generated is:
select * from empinfo t0, phone t1 where t0.empid=t1.empid and
t1.phone='11'
which does not return all the phone numbers of the employee
having phone number '11'.
_Case 2_: If I set the selection criteria after adding the join
attribute the query generated is:
select * from empinfo t0, phone t1, phone t2, where
t0.empid=t1.empid and t1.phone='11' and t2.empid=t0.empid
which returns all the phone numbers of the employee having phone
number '11'.
Also in case 1 if I generate the query for the second time with
the same session, the query of case 2 is generated, however
again not all phone numbers of the employee having phone number
'11' are generated (*perhaps due to caching?*)
If I do not set any selection criteria the first time I query,
then all the information is returned the first time as expected.
If I now use the sequence of Case 1 for creating a query in the
same session then the correct result is obtained. *How to
explain this?*
*Is this behavior expected? Why is it important to add the join
attribute before setting the selection criteria?*
*Could you please point me to the relevant documentation?*
Thanks in Advance!
--
Thanks and Regards
Rohit Banga
Member Technical Staff
Oracle Server Technologies
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Thanks and Regards
Rohit Banga
Member Technical Staff
Oracle Server Technologies
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