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.TITLE FROM
> > 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]
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>
