Hi Adriano,
There are test cases like - testReadOrdersAndDetails2(
org.apache.tuscany.das.rdb.test.CompoundKeyTests)
which were failing when the code was throwing exception for any null data in
PK. With the
OUTER JOIN logic (no exception when all columns are null including PK , just
omit the DO),
these cases are succeeding now. But for the sake of completeness, added new
testOuterJoin() case.
Also, I added a case where in parent-child - child PK is null and the row
as such has some data(testNullDataInPK()). This throws exception. Please
review the latest
patch (Aug 6) for this.
On 8/4/07, Adriano Crestani <[EMAIL PROTECTED]> wrote:
>
> Hi Amita,
>
> Have you added the case when the row is completely null on last patch
> you've
> uploaded on JIRA-1464?
>
> Regards,
> Adriano Crestani
>
> On 8/3/07, Adriano Crestani <[EMAIL PROTECTED]> wrote:
> >
> > Hi Amita,
> >
> > Great work you are doing : ). You are correct about the outer join case,
> I
> > hadn't remember this use case. Yes, DAS should ignore a row completely
> null,
> > but only when it's completely null, any other data in it, DAS should
> throw
> > an exception.
> >
> > Thanks for the explanation about the static id column. I wasn't aware
> > enough about how static DO works : (
> >
> > Regards,
> > Adriano Crestani
> >
> > On 8/3/07, Amita Vadhavkar <[EMAIL PROTECTED]> wrote:
> > >
> > > In RDBMS and in DAS OUTER JOINs are used quite frequently. By
> definition
> > > it means, all rows from parent and matching rows from child. So, there
> > > is a
> > > chance for having complete null rows from child and that is the
> purpose
> > > of
> > > OUTER JOIN.
> > >
> > > So there are different situations
> > > 1) complete child row is null (outer join case)- we should allow this,
> > > so
> > > that outer joins work :)
> > > 2) PK(single/compound) in child row is null, but some other columns
> have
> > >
> > > data - we should flag this case and throw exception
> > > 3) PK(single/compound) in parent row is null, but some other columns
> > > have
> > > data - we should flag this case and throw exception
> > > 4) complete parent row is null - allow :) , as anyways relationship
> will
> > > not
> > > be formed
> > >
> > > If we do not allow 1) 20 existing cases which use OUTER JOIN will
> fail,
> > > otherwise
> > > all existing cases succeed.
> > >
> > > So, instead of giving exception for Null data in PK columns, we can
> > > avoid
> > > those DOs in final Graph.
> > >
> > > But, absence of PK column (Type) itself from Result Set is another
> case,
> > > where there is no way to form the correct graph irrespective of values
> > > in
> > > the columns.
> > >
> > > Due to the above reasons, I am not doing the change in logic over
> Jul31
> > > patch, but
> > > I am still uploading a new patch to fix 2 minor issues
> > > 1) name of the new xml file referred in test case was
> > > companyNoIDMappingWithConverters
> > > changing it to
> > > companynoidMappingWithConverters
> > >
> > > 2)if check in ResultSetProcessor.addRowToGraph() is made more complete
> > > to
> > > ensure
> > > no corner cases miss
> > >
> -----------------------------------------------------------------------------------------------------------------------------------
> > >
> > > For the other question in JIRA-1464, please see the below
> explaination:-
> > > Question:
> > > As ID column being considered primary key is a Convention Over
> > > Configuration
> > > issue, I think the user shouldn't need to declare it anywhere, cause
> DAS
> > >
> > > should recognize it anyway. What do you think?
> > >
> > > Ans:
> > > This will be true for Dynamic DO case, typically a query will be
> > > executed
> > > with ID column. COC will determine to treat it as PK. It will be used
> > > when
> > > registering new Type and Properties (SDO) in SDO context. And so when
> > > populating data in DOs, ID property will be found.
> > >
> > > But the change is done in company.xsd to take care of static DO
> > > scenario.
> > > Here, companyMappingWithConverters.xml refers to static model
> > > company.xsdand the generation
> > > of equiv java classes is before runtime. So, if ID is missing in
> > > company.xsd,
> > > ID will
> > > not be created in CompanyType...generated classes. After that in
> > > runtime,
> > > DAS will not be
> > > creating new Types and Properties for company as these are already in
> > > SDO
> > > context.
> > > Thus when populating DO with values from query, ID propery will not be
> > > found
> > > and exception will be thrown. Checked the same and get below
> exception.
> > > Example:-
> > > testSimpleStatic(org.apache.tuscany.das.rdb.test.CompanyTests) Time
> > > elapsed: 0.
> > > 18 sec <<< ERROR!
> > > java.lang.RuntimeException: Type CompanyType does not contain a
> property
> > > named I
> > >
> > > Regards,
> > > Amita
> > >
> > > On 8/2/07, Adriano Crestani <[EMAIL PROTECTED]> wrote:
> > > >
> > > > Yes, I think it should fail, once DAS shouldn't omit a data from
> the
> > > > user.
> > > > Cause, if the pk has null pk, it means it doesn't have an id and
> > > cannot be
> > > > guaranteed its uniqueness. I think maybe DAS should not throw the
> > > > exception,
> > > > but needs to warn the user when any row is omitted, however I don't
> > > think
> > > > it
> > > > is a good approach at all. My suggestion is that it should fail
> > > whenever
> > > > is
> > > > found a null pk.
> > > >
> > > > Regards,
> > > > Adriano Crestani
> > > >
> > > > On 8/2/07, Amita Vadhavkar < [EMAIL PROTECTED]> wrote:
> > > > >
> > > > > There is a bit of confusion around the
> > > > RecursiveTests.testReadEngineParts
> > > > > ()
> > > > > , in the context of this fix.
> > > > >
> > > > > Below is the data for tables, queries etc.
> > > > >
> > > > > sql return:-
> > > > > *1 Engine 1 - 2 Block 1
> 1 -
> > > > > - - -
> > > > > *1 Engine 1 - 3 Cam Soft 2 1 -
> -
> > > > > - -
> > > > > 1 Engine 1 - 4 Piston 8
> 1 5
> > > > Piston
> > > > > Ring 2 4
> > > > >
> > > > > table data:-
> > > > > id name qty parent id
> > > > > 1 Engine 1 -
> > > > > 2 Block 1 1
> > > > > 3 Cam Soft 2 1
> > > > > 4 Piston 8 1
> > > > > 5 Piston Ring 2 4
> > > > >
> > > > > query:-
> > > > > SELECT
> > > > > P1.ID,
> > > > > P1.NAME,
> > > > > P1.QUANTITY ,
> > > > > P1.PARENT_ID,
> > > > > P2.ID,
> > > > > P2.NAME,
> > > > > P2.QUANTITY,
> > > > > P2.PARENT_ID,
> > > > > P3.ID,
> > > > > P3.NAME,
> > > > > P3.QUANTITY,
> > > > > P3.PARENT_ID
> > > > > FROM
> > > > > APP.PART AS P1 LEFT OUTER JOIN APP.PART AS P2
> > > > > ON P1.ID = P2.PARENT_ID
> > > > > LEFT OUTER JOIN APP.PART AS P3
> > > > > ON P2.ID = P3.PARENT_ID
> > > > > WHERE
> > > > > P1.ID = 1
> > > > >
> > > > > See the recursiveTests. here the recursion occurs 3 times on the
> > > same
> > > > > (part)
> > > > > table and total 5 DOs should be formed in mem. (pre-existing
> case).
> > > Now
> > > > > see
> > > > > ResultSetProcessor.addRowToGraph(). if we take null data in pk as
> > > > > exception,
> > > > > the rows from
> > > > > sql return above marked with *, will cause the whole query to fail
> > > and
> > > > so
> > > > > the recursiveTests
> > > > > will fail.
> > > > >
> > > > > But if we do some adjustments to allow this case to succeed, there
> > > can
> > > > be
> > > > > other situations
> > > > > where not throwing exception for null data in PK for any row can
> > > cause
> > > > > problem (incomplete/wrong results). So, is it better to make
> > > > > RecursiveTests
> > > > > fail? Suggestions?
> > > > >
> > > > > Regards,
> > > > > Amita
> > > > >
> > > > > On 7/28/07, Adriano Crestani < [EMAIL PROTECTED]> wrote:
> > > > > >
> > > > > > It seems ok Amita ; )
> > > > > >
> > > > > > Adriano Crestani
> > > > > >
> > > > > > On 7/27/07, Amita Vadhavkar < [EMAIL PROTECTED]> wrote:
> > > > > > >
> > > > > > > Hi Adriano,
> > > > > > > Yes, so in summary , trying to do following -
> > > > > > >
> > > > > > > 1) select missing complete or partial PK for any of the tables
> > > > > involved-
> > > > > > > exception
> > > > > > > 2) if any table in select has no PK in config and no ID column
> > > in
> > > > > > > config/select - exception
> > > > > > > 3) if any table in select has no PK in config and has ID
> column
> > > in
> > > > > > config
> > > > > > > -
> > > > > > > exception
> > > > > > > 4) if any table in select has no PK in config but has ID
> column
> > > in
> > > > > > SELECT
> > > > > > > -
> > > > > > > success
> > > > > > >
> > > > > > > Regards,
> > > > > > > Amita
> > > > > > >
> > > > > > > On 7/27/07, Adriano Crestani <[EMAIL PROTECTED]>
> wrote:
> > > > > > > >
> > > > > > > > I had the same problem on DAS C++, now it's throwing an
> > > exception
> > > > > when
> > > > > > > it
> > > > > > > > finds a row that does not contain all the pk columns.
> > > > > > > >
> > > > > > > > I'm not used to the DAS Java, but I will explain how I did
> it
> > > on
> > > > DAS
> > > > > > > C++,
> > > > > > > > maybe this can help you ; )
> > > > > > > >
> > > > > > > > It reads the ResultSet metadata to find the pk columns. If
> the
> > > PK
> > > > is
> > > > > > > > defined
> > > > > > > > on the config, so it look for the columns defined as pk on
> the
> > >
> > > > > config.
> > > > > > > In
> > > > > > > > case it does not find the pk column(or columns if it is a
> > > compound
> > > > > > pk),
> > > > > > > it
> > > > > > > > looks for the ID columns according to DAS Convention Over
> > > > > > Configuration
> > > > > > > > rules. Otherwise it throws the exception.
> > > > > > > >
> > > > > > > > Does it help? : )
> > > > > > > >
> > > > > > > > Regards,
> > > > > > > > Adriano Crestani
> > > > > > > >
> > > > > > > > On 7/27/07, Amita Vadhavkar <[EMAIL PROTECTED]>
> wrote:
> > > > > > > > >
> > > > > > > > > Further on this,
> > > > > > > > > Need to consider single and compound PKs case.
> > > > > > > > > When select does not include complete PK (all PK columns
> > > from
> > > > > > compound
> > > > > > > > PK)
> > > > > > > > > ,
> > > > > > > > > DAS needs to throw exception.
> > > > > > > > >
> > > > > > > > > As a fix proposing below changes:-
> > > > > > > > >
> > > > > > > > > A>In ResultMetadata - introduce new HashMap
> > > tableToPrimaryKeys ,
> > > > > > fill
> > > > > > > it
> > > > > > > > > during constuctor
> > > > > > > > > and provide get method - getAllPKsForTable(tableName).
> > > > > > > > >
> > > > > > > > > B> In ResultSetRow - add method
> > > > > > > > > checkResultSetMissesPK(allTableNamesFromQueryResultSet)
> > > > > > > > > which will take each table and check if all PKs are there
> in
> > > > > result
> > > > > > > set.
> > > > > > > > > If
> > > > > > > > > not it will mark that TableData with hasValidPKs=FALSE.
> > > > > > > > >
> > > > > > > > > C> There is already another check in TableData.addData(),
> > > which
> > > > > > marks
> > > > > > > > this
> > > > > > > > > flag FALSE, if any PK in result set has NULL data.
> > > > > > > > >
> > > > > > > > > B> and C> together will provide complete check
> > > > > > > > >
> > > > > > > > > D>In ResultSetRow, call,
> > > > > > > > > checkResultSetMissesPK(allTableNamesFromQueryResultSet)
> from
> > >
> > > > > > > > processRow()
> > > > > > > > > and processRecursiveRow(). With this, all TableData will
> be
> > > set
> > > > > with
> > > > > > > > > proper
> > > > > > > > > hasValidPK, during ResultSetProcessor.processResultSet()
> and
> > > > > > > > consequently,
> > > > > > > > > in ResultSetProcessor.addRowToGraph() will be able to do
> > > > > judgement
> > > > > > if
> > > > > > > > any
> > > > > > > > > table is missing PK, in which case DAS will throw
> > > > RuntimeException
> > > > > > and
> > > > > > > > > will
> > > > > > > > > not form DataGraph.
> > > > > > > > >
> > > > > > > > > Any comments/suggestions? Based on this I will work on
> patch
> > > for
> > > > > > > > > JIRA-1464.
> > > > > > > > >
> > > > > > > > > Regards,
> > > > > > > > > Amita
> > > > > > > > >
> > > > > > > > > On 7/19/07, haleh mahbod <[EMAIL PROTECTED]> wrote:
> > > > > > > > > >
> > > > > > > > > > It is best to throw an exception for PK not being there,
> > > > > otherwise
> > > > > > > an
> > > > > > > > > > empty
> > > > > > > > > > result set can have two meaning:Empty or something went
> > > wrong
> > > > > > > > > >
> > > > > > > > > > On 7/18/07, Adriano Crestani <[EMAIL PROTECTED]
> >
> > > > wrote:
> > > > > > > > > > >
> > > > > > > > > > > Amita,
> > > > > > > > > > >
> > > > > > > > > > > There is now way for DAS to keep
> > > > > > > > the relationship data consistence
> > > > > > > > > > if
> > > > > > > > > > > both, pk and fk, are not completely defined. Without
> > > them
> > > > DAS
> > > > > > > cannot
> > > > > > > > > > > predict
> > > > > > > > > > > the relationship.
> > > > > > > > > > >
> > > > > > > > > > > As Brent said, I think it could throw an exception
> when
> > > the
> > > > PK
> > > > > > is
> > > > > > > > > > missing,
> > > > > > > > > > > no matter if there are relationships or not. Because,
> as
> > > far
> > > > > as
> > > > > > I
> > > > > > > > > know,
> > > > > > > > > > a
> > > > > > > > > > > table that has no complete PK retrieved on the
> > > ResultSet is
> > > > > > being
> > > > > > > > > > omitted
> > > > > > > > > > > from the graph and I don't think this is a good
> > > approach.
> > > > > > > > > > >
> > > > > > > > > > > But when only the fk is missing, I think it is ok to
> > > omit
> > > > the
> > > > > > > > > > relationship
> > > > > > > > > > > between the data objects on the graph. This way the
> user
> > > has
> > > > > the
> > > > > > > > > option
> > > > > > > > > > to
> > > > > > > > > > > decide if the references(relationships) will be
> included
> > > or
> > > > > not
> > > > > > on
> > > > > > > > the
> > > > > > > > > > > graph.
> > > > > > > > > > >
> > > > > > > > > > > Regards,
> > > > > > > > > > > Adriano Crestani
> > > > > > > > > > >
> > > > > > > > > > > On 7/18/07, Brent Daniel <[EMAIL PROTECTED]>
> wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > Amita,
> > > > > > > > > > > >
> > > > > > > > > > > > Definitely, the DAS should enforce the requirement
> > > that
> > > > the
> > > > > PK
> > > > > > > > > should
> > > > > > > > > > > > be returned for each table in the results. I would
> > > > consider
> > > > > > this
> > > > > > > a
> > > > > > > > > > > > case where the DAS should throw an exception.
> > > > > > > > > > > >
> > > > > > > > > > > > Brent
> > > > > > > > > > > >
> > > > > > > > > > > > On 7/18/07, Amita Vadhavkar <
> > > [EMAIL PROTECTED]>
> > > > > wrote:
> > > > > > > > > > > > > Sorry for the leng thy mail....
> > > > > > > > > > > > >
> > > > > > > > > > > > > Tried to check the case when the database has
> > > > parent-child
> > > > > > > > tables
> > > > > > > > > > and
> > > > > > > > > > > > DAS
> > > > > > > > > > > > > SELECT Command may/may not
> > > > > > > > > > > > > contain the PKs of the tables. And found some
> quite
> > > > > > confusing
> > > > > > > > > > > > cases/results,
> > > > > > > > > > > > > which are effectively giving
> > > > > > > > > > > > > user a wrong impression of the data in tables.
> > > > > > > > > > > > >
> > > > > > > > > > > > > Looks like there are places where we are allowing
> > > > partial
> > > > > > > > results,
> > > > > > > > > > > wrong
> > > > > > > > > > > > > association in parent and child rows.
> > > > > > > > > > > > > As RDB DAS logic revolves around PKs, can we state
> > > > clearly
> > > > > > > that
> > > > > > > > > > > > > "When Query SELECT does not include PK for a
> table,
> > > the
> > > > > data
> > > > > > > > graph
> > > > > > > > > > > will
> > > > > > > > > > > > be
> > > > > > > > > > > > > empty for that table"
> > > > > > > > > > > > > ? i.e. in the below analysis, instead of giving
> > > > > > wrong/partial
> > > > > > > > > > result,
> > > > > > > > > > > at
> > > > > > > > > > > > > least consistently give no result?
> > > > > > > > > > > > > And make necessary code corrections to adhere to
> > > this
> > > > > > > statement?
> > > > > > > > > > > > >
> > > > > > > > > > > > > Or any alternative approaches?
> > > > > > > > > > > > >
> > > > > > > > > > > > > What DAS C++ is doing for this case? Just curious.
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > Say, take below data -
> > > > > > > > > > > > > Parent: SINGER(ID, NAME), Child:SONG (ID, TITLE,
> > > > SINGERID)
> > > > > > > > > > > > > Data:
> > > > > > > > > > > > > SINGER
> > > > > > > > > > > > > ID NAME
> > > > > > > > > > > > > --------------------
> > > > > > > > > > > > > 1 Jonh
> > > > > > > > > > > > > 2 Jane
> > > > > > > > > > > > >
> > > > > > > > > > > > > SONG
> > > > > > > > > > > > > ID TITLE SINGERID
> > > > > > > > > > > > > -------------------------------------
> > > > > > > > > > > > > 10 ABCD 1
> > > > > > > > > > > > > 20 Lamb 1
> > > > > > > > > > > > > 30 La ra ra 2
> > > > > > > > > > > > >
> > > > > > > > > > > > > There are total 8 cases that I can see. viz.
> > > > > > > > > > > > >
> > > > > > > > > > > > > No relationship in config
> > > > > > > > > > > > > --------------------------------------------------
> > > > > > > > > > > > > parent PK in SEL child PK in SEL Result
> > > > > > > > > > > > >
> > > > > > > > > >
> > > > > > >
> > > >
> ----------------------------------------------------------------------
> > > > > > > > > > > > > [1]
> > > > present present correct
> > > > > > > > > > > > > [2]
> > > present missing wrong
> > > > > > > > > > > > > [3]
> > > missing present wrong
> > > > > > > > > > > > > [4] missing missing
> > > wrong
> > > > > > > > > > > > >
> > > > > > > > > > > > > Relationship in config
> > > > > > > > > > > > > [5] present present
> > > correct
> > > > > > > > > > > > > [6] present missing
> > > wrong
> > > > > > > > > > > > > [7] missing present
> > > wrong
> > > > > > > > > > > > > [8]
> > > missing missing wrong
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > When relationship is not defined in DAS Config
> > > > > > > > > > > > > DAS Client code:
> > > > > > > > > > > > > ----------------
> > > > > > > > > > > > > DAS das = DAS.FACTORY.createDAS(getConfig("cfg.xml
> > > "),
> > > > > > > > > > > getConnection());
> > > > > > > > > > > > > Command select = das.getCommand
> > > ("withNoRel-5/6/7/8");
> > > > > > > > > > > > > DataObject root = select.executeQuery();
> > > > > > > > > > > > > List singers = root.getList("SINGER");
> > > > > > > > > > > > > if(singers != null){
> > > > > > > > > > > > > System.out.println("Singer
> > > > size:"+singers.size());
> > > > > > > > > > > > > for(int i=0; i<singers.size(); i++){
> > > > > > > > > > > > > System.out.println("SINGER NAME:"+
> > > > > > > > > > > > > ((DataObject)singers.get(i)).getString("NAME"));
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > > > List songs = root.getList("SONG");//as there is no
> > > > > > > relationship
> > > > > > > > > > > > > (explicit/implicit)
> > > > > > > > > > > > >
> > > > > > > > > > > > > if(songs != null){
> > > > > > > > > > > > > System.out.println("Songs size "+songs
> > > .size());
> > > > > > > > > > > > > for(int ii=0; ii<songs.size(); ii++){
> > > > > > > > > > > > > System.out.println("SONG TITLE:"+
> > > > > > > > > > > > > ((DataObject)songs.get(ii)).getString("TITLE"));
> > > > > > > > > > > > > }
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > Result:
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > [1] SELECT SINGER.ID, SINGER.NAME, SONG.ID,
> > > > SONG.TITLEFROM
> > > > > > > > > SINGER,
> > > > > > > > > > > SONG
> > > > > > > > > > > > > WHERE SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:2
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > SINGER NAME:Jane
> > > > > > > > > > > > > Songs size 3
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > > SONG TITLE:Lamb
> > > > > > > > > > > > > SONG TITLE:La ra ra
> > > > > > > > > > > > >
> > > > > > > > > > > > > [2] SELECT SINGER.ID, SINGER.NAME, SONG.TITLE FROM
> > > > SINGER,
> > > > > > > SONG
> > > > > > > > > > WHERE
> > > > > > > > > > > > > SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:2
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > SINGER NAME:Jane
> > > > > > > > > > > > > Songs size 1
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > >
> > > > > > > > > > > > > [3] SELECT SINGER.NAME, SONG.ID, SONG.TITLE FROM
> > > SINGER,
> > > > > > SONG
> > > > > > > > > WHERE
> > > > > > > > > > > > > SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:1
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 3
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > > SONG TITLE:Lamb
> > > > > > > > > > > > > SONG TITLE:La ra ra
> > > > > > > > > > > > >
> > > > > > > > > > > > > [4] SELECT SINGER.NAME , SONG.TITLE FROM SINGER,
> > > SONG
> > > > WHERE
> > > > > > > > > SINGER.ID=
> > > > > > > > > > > > > SONG.SINGERID
> > > > > > > > > > > > > Singer size:1
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 1
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > When relationship one-to-many (sing) is defined in
> > > DAS
> > > > > > Config
> > > > > > > > > > > > > DAS Client code:
> > > > > > > > > > > > > ----------------
> > > > > > > > > > > > > DAS das = DAS.FACTORY.createDAS (getConfig("
> cfg.xml
> > > "),
> > > > > > > > > > > getConnection());
> > > > > > > > > > > > > Command select = das.getCommand
> ("withRel-1/2/3/4");
> > > > > > > > > > > > > DataObject root = select.executeQuery();
> > > > > > > > > > > > > List singers = root.getList("SINGER");
> > > > > > > > > > > > > if(singers != null){
> > > > > > > > > > > > > System.out.println("Singer
> > > size:"+singers.size());
> > > > > > > > > > > > > for(int i=0; i<singers.size(); i++){
> > > > > > > > > > > > > System.out.println ("SINGER NAME:"+
> > > > > > > > > > > > > ((DataObject)singers.get(i)).getString("NAME"));
> > > > > > > > > > > > >
> > > > > > > > > > > > > List songs =
> > > > > > > > ((DataObject)singers.get(i)).getList("sing");
> > > > > > > > > > > //use
> > > > > > > > > > > > > relationship
> > > > > > > > > > > > > if(songs != null){
> > > > > > > > > > > > > System.out.println("Songs size "+songs
> > > > > .size()+"
> > > > > > > for
> > > > > > > > > > > singer
> > > > > > > > > > > > >
> :"+((DataObject)singers.get(i)).getString("NAME"));
> > > > > > > > > > > > > for(int ii=0; ii<songs.size(); ii++){
> > > > > > > > > > > > > System.out.println("SONG TITLE:"+
> > > > > > > > > > > > > ((DataObject)songs.get(ii)).getString("TITLE"));
> > > > > > > > > > > > > }
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > > > }
> > > > > > > > > > > > > }
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > Result:
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > > [5] SELECT SINGER.ID, SINGER.NAME, SONG.ID,
> > > > SONG.TITLEFROM
> > > > > > > > > SINGER,
> > > > > > > > > > > SONG
> > > > > > > > > > > > > WHERE SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:2
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 2 for singer :John
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > > SONG TITLE:Lamb
> > > > > > > > > > > > > SINGER NAME:Jane
> > > > > > > > > > > > > Songs size 1 for singer :Jane
> > > > > > > > > > > > > SONG TITLE:La ra ra
> > > > > > > > > > > > >
> > > > > > > > > > > > > [6] SELECT SINGER.ID , SINGER.NAME, SONG.TITLEFROM
> > > > SINGER,
> > > > > > > SONG
> > > > > > > > > > WHERE
> > > > > > > > > > > > > SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:2
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 0 for singer :John
> > > > > > > > > > > > > SINGER NAME:Jane
> > > > > > > > > > > > > Songs size 1 for singer :Jane
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > >
> > > > > > > > > > > > > [7] SELECT SINGER.NAME, SONG.ID, SONG.TITLE FROM
> > > SINGER,
> > > > > > SONG
> > > > > > > > > WHERE
> > > > > > > > > > > > > SINGER.ID = SONG.SINGERID
> > > > > > > > > > > > > Singer size:1
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 3 for singer :John
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > > SONG TITLE:Lamb
> > > > > > > > > > > > > SONG TITLE:La ra ra
> > > > > > > > > > > > >
> > > > > > > > > > > > > [8] SELECT SINGER.NAME, SONG.TITLE FROM SINGER,
> SONG
> > > > WHERE
> > > > > > > > > SINGER.ID=
> > > > > > > > > > > > > SONG.SINGERID
> > > > > > > > > > > > > Singer size:1
> > > > > > > > > > > > > SINGER NAME:John
> > > > > > > > > > > > > Songs size 1 for singer :John
> > > > > > > > > > > > > SONG TITLE:ABCD
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> -------------------------------------------------------------------------------------
> > > > > > > > > > > > >
> > > > > > > > > > > > > Regards,
> > > > > > > > > > > > >
> > > > > > > > > > > > > Amita
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > >
> > > > > >
> > > ---------------------------------------------------------------------
> > > > > > > > > > > > To unsubscribe, e-mail:
> > > > > [EMAIL PROTECTED]
> > > > > > > > > > > > For additional commands, e-mail:
> > > > > > [EMAIL PROTECTED]
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> >
>
