Re: Still no luck with this query

Mon, 15 Mar 2004 10:09:59 -0800

hi john,

a very important issue doing or-mapping is having a clean object-model and clean
db-schema. you say service has to point to a serviceinterest (1:1), but why is it actually a 1:n relation ship ? what is the meaning of the columns targetmsid and interestmsid. to me this table looks like an m:n-connection-table, like the person_project table in the ojb-testcases.

jakob

[EMAIL PROTECTED] wrote:
Thank you so much Jakob. You help lots of people here. Hopefully when I feel I understand OR mappings a bit better I can help some as well.

I had not responded right away because I have been thinking about your solution. You turned the problem upside down making the keys match which works.

The only downside to the solution which has been having me do that thinking part is that the serviceinterest table/object "was" kinda generic. By turning this upside down, I now map a seperate serviceinterest object to each service rather then a service to a generic serviceinterest. Though not a big deal it doubles the number of required mappings and reduces a bit of the abstraction. It also creates/stores more objects then I was hoping it would because i was not hoping ot have to hold onto all of the serviceinterest data, but just the service data (rstep1 is just one service type in the bigger problem).

All in all, however, this is a HUGE improvement over not being able to get the query to work at all!!!

Thank you sir.

JohnE


----- Original Message -----
From: Jakob Braeuchi <[EMAIL PROTECTED]>
Date: Friday, March 12, 2004 12:13 pm
Subject: Re: Still no luck with this query


hi john,

[EMAIL PROTECTED] wrote:


Sorry for the confusion. I tried to abbreviate to make it

easier to read.


In the end, I want to do this query:

       SELECT r.msid, r.rtitle, r.brief
       FROM rstep1 r, serviceinterest si
       WHERE ((si.targetmsid = 101)
             AND (si.interestmsid = r.msid))



Based on these two tables and the repository I gave previously:
CREATE TABLE rstep1 (
msid BIGINT(20) NOT NULL,
rtitle VARCHAR(70) NOT NULL,
brief VARCHAR(255) NULL,
PRIMARY KEY(msid),
)
CREATE TABLE serviceinterest (
targetmsid BIGINT(20) UNSIGNED NOT NULL,
interestmsid BIGINT(20) UNSIGNED NOT NULL,
targetmid BIGINT(20) UNSIGNED NOT NULL,
interestmid BIGINT(20) UNSIGNED NOT NULL,
PRIMARY KEY(targetmsid, interestmsid)
)



si.targetmsid=101, the subquery and one part of the

serviceinterest primary key, should generate a list of serviceinterests.>

I want to return the one-to-one associated rstep1

(RServiceInterestVO) for each of the those serviceinterests that were generated.

why don't you define a 1:1 relationship pointing from ServiceInterest to RServiceInterestVO. imo the relationship pointing in the other direction (RServiceInterestVO to ServiceInterest) should be a 1:n relationship.

<class-descriptor class="com.model.services.interest.RServiceInterestVO" table="rstep1">

<field-descriptor
name="memberServiceId"
column="msid"
jdbc-type="BIGINT"
primarykey="true"
/>
...
<collection-descriptor
name="serviceInterests" class-ref="com.model.memberservice.ServiceInterestVO"
auto-retrieve="true"
auto-update="false"
auto-delete="false">
<inverse-foreignkey field-ref="targetMemberServiceId"/>
</collection-descriptor>
</class-descriptor>

<class-descriptor class="com.model.memberservice.ServiceInterestVO" table="serviceinterest">

<field-descriptor
name="targetMemberServiceId"
column="targetmsid"
jdbc-type="BIGINT"
primarykey="true"
/>
<field-descriptor
name="interestMemberServiceId"
column="interestmsid"
jdbc-type="BIGINT"
primarykey="true"
/>
...
<reference-descriptor
name="targetService" class-ref="com.model.memberservice.RServiceInterestVO"
auto-retrieve="true"
auto-update="false"
auto-delete="false">
<foreignkey field-ref="targetMemberServiceId"/>
</reference-descriptor>

</class-descriptor>


then it should be possible to query:

Criteria crit = new Criteria();
crit.addEqualTo("serviceInterests.targetMemberServiceId", 101);
Query query = new QueryByCriteria(RServiceInterestVO.class, crit);
broker.getCollectionByQuery(query);

jakob


crit.addEqualTo("serviceInterest.targetMemberServiceId", 101);
crit.addEqualToField("serviceInterest.interestMemberServiceId",

"memberServiceId");>

Yes I am trying to join with this addEqualToField, but notice

onto the 2nd half of the primary key.


I know my mapping is wrong, bit I don't know how to give a

correct mapping for this problem. That is where my problem lies. In every other query I have done, there was a simple one to one primary key mapping that INNER JOIN worked well on. Here, the primary key is not fully used in the subquery and actually prevents this from working.

Hense I am asking for a new idea or direction. I don't know

how to proceed. I am trying to learn.

JohnE



----- Original Message -----
From: Jakob Braeuchi <[EMAIL PROTECTED]>
Date: Thursday, March 11, 2004 1:17 pm
Subject: Re: Still no luck with this query



hi john,

you have a 1:1-relationship pointing from RServiceInterestVO to ServiceInterestVO, is this correct ? a similar relationship can

be

found in the samples (ProductGroup to Article).
the pk of RServiceInterestVO is used as fk to ServiceInterestVO

in

your repository. but the comment says it's wrong.

according to the repository each class has a single pk; but the table serviceinterest uses a combined pk ? and i cannot find a create table for rstep1. pk definition in create table and the repository must match !

crit.addEqualTo("serviceInterest.targetMemberServiceId", jMsid);
crit.addEqualToField("serviceInterest.interestMemberServiceId", "memberServiceId");
dou you try to force a join with addEqualToField ?

jakob

[EMAIL PROTECTED] wrote:



Thank you for responding Jakob.

Again this is the query I would like:

      SELECT r.msid, r.rtitle, r.brief
      FROM rstep1 r, serviceinterest si
      WHERE ((si.targetmsid = 101)
            AND (si.interestmsid = r.msid))


Below was my first of many attempts to solve this problem, but

it wouldn't work right using RC4 because it tries to form the INNER JOIN from the memberServiceId to the first of two part primary key in the second table. I had not tried this particular method in RC5, but tried other methods using RC5.


I know below is wrong, but I don't know the right strategy for

what I need. I can't seem to figure out how to handle

subqueries

not off the primary key.


I want a collection of these back:

<class-descriptor

class="com.model.services.interest.RServiceInterestVO"

table="rstep1">>>

  <field-descriptor
      name="memberServiceId"
      column="msid"
      jdbc-type="BIGINT"
      primarykey="true"
  />
  <field-descriptor
      name="rTitle"
      column="rtitle"
      jdbc-type="VARCHAR"
  />
  <field-descriptor
      name="brief"
      column="brief"
      jdbc-type="VARCHAR"
  />



<!-- This would be wrong, as I don't want to go off of

ServicenterestVO's> primary key, but use this object in a subquery. -->

  <reference-descriptor
          name="serviceInterest"
          class-ref="com.model.memberservice.ServiceInterestVO"
          auto-retrieve="true"
          auto-update="false"
          auto-delete="false">
      <foreignkey field-ref="memberServiceId"/>
  </reference-descriptor>

</class-descriptor>





This is what the subquery table looks like:


<class-descriptor

class="com.model.memberservice.ServiceInterestVO"

table="serviceinterest">>>

        <field-descriptor
      name="targetMemberServiceId"
      column="targetmsid"
      jdbc-type="BIGINT"
      primarykey="true"
  />
        <field-descriptor
      name="targetMemberId"
      column="targetmid"
      jdbc-type="BIGINT"
      indexed="true"
  />
        <field-descriptor
      name="interestMemberServiceId"
      column="interestmsid"
      jdbc-type="BIGINT"
      primarykey="true"
  />
        <field-descriptor
      name="interestMemberId"
      column="interestmid"
      jdbc-type="BIGINT"
      indexed="true"
  />
</class-descriptor>





This failed as well as other things:

crit.addEqualTo("serviceInterest.targetMemberServiceId",

jMsid);> crit.addEqualToField("serviceInterest.interestMemberServiceId",

"memberServiceId");>>

Collection result =

GenericDAO.getInstance().findCollectionByCriteria(objectClass,

crit);>>







----- Original Message -----
From: Jakob Braeuchi <[EMAIL PROTECTED]>
Date: Wednesday, March 10, 2004 1:25 pm
Subject: Re: Still no luck with this query




hi john,

you should at least provide some information about the

repository


you use.

jakob

[EMAIL PROTECTED] wrote:




Dear all,

Maybe I wasn't asking my question well because it had not

gained


a response in about a week. Maybe I am missing something very simple, but I am still pretty new to any kinda OR-mappings and

I

have nobody who can help but this list. Rather then try to explain the 4 different ways I tried to solve it again, how

might


people with better understanding. I can not find an answer

to

this in the mailing lists nor in the docs. If you have a reference, please give me a pointer.



I am trying to get a listing of all of the services

('aservice')


that are interested in my particular service (having id 101).



// The query I would like agressively abreviated:
SELECT r.msid, r.rtitle, r.brief

FROM aservice r, serviceinterest si 


WHERE ((si.targetmsid = 101)
   AND (si.interestmsid = r.msid))


// I want a collection of these returned
CREATE TABLE aservice (
msid BIGINT(20) NOT NULL,
rtitle VARCHAR(70) NOT NULL,
brief VARCHAR(255) NULL,
PRIMARY KEY(msid),
)


// Note a duo key that should not be referenced in whole by

aservice:> CREATE TABLE serviceinterest (



targetmsid BIGINT(20) UNSIGNED NOT NULL,
interestmsid BIGINT(20) UNSIGNED NOT NULL,
PRIMARY KEY(targetmsid, interestmsid)
)


I have been having problems because of foreign keys and how

INNER JOIN seems to work with this query.



Thank you if you can. I will gladly post more detailed

information or email the code as need be.



JohnE
[EMAIL PROTECTED]





--------------------------------------------------------------

--

-


----



To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



---------------------------------------------------------------

--

--


--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]





----------------------------------------------------------------

-

----


To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



-----------------------------------------------------------------

--

--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]





-----------------------------------------------------------------

----

To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



-------------------------------------------------------------------
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]





---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]



---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to