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Posted to dev@tuscany.apache.org by Amita Vadhavkar <am...@gmail.com> on 2007/07/12 09:32:12 UTC
[RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Hi,
Recently there came up a requirement from user (ref. JIRA-1355), when the
user
was attempting DAS.createCommand(sql) in Oracle. As of today, in RDB DAS,
user
can specify ResultDescriptor using external Config File containing Commands.
But
there is no provision for user to pass ResultDescriptor for a Command, when
it is
created as above (dynamic - without Config File). As, for Oracle and some
other
databases, when database meta data is not sufficient, DAS requires user to
supply
ResultDescriptor as a substitute. For taking care of such situations, DAS
needs to
expose Command.set/getResultDescriptors(List <ResultDescriptor>).
One rule to be adhered when using this API will be sequencing of
ResultDescriptors
in the input List.The sequence in the List <ResultDescriptor> has to be in
sync
with the sequence of parameters in "sql". With this, I guess it will be a
really
useful and handy functionality, that RDB DAS needs to consider.
Thoughts?
Regards,
Amita
Re: [RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Posted by Amita Vadhavkar <am...@gmail.com>.
Please review JIRA-1465 patch for this
Regards,
Amita
On 8/7/07, Amita Vadhavkar <am...@gmail.com> wrote:
>
> Oops, I guess after the first maill, rest of the mails were not sent to
> dev list.
>
> Regards,
> Amita
>
> On 8/7/07, Adriano Crestani <ad...@apache.org> wrote:
> >
> > Yes, but I suggest the name columnIndex or just index instead of
> > columnIdx.
> >
> > Regards,
> > Adriano Crestani
> >
> > On 8/6/07, Amita Vadhavkar <amita.vadhavkar@gmail.com > wrote:
> > >
> > > Hi Adriano,
> > > Just to get it clear, at present, result descriptor defn is
> > > <xsd:complexType name="ResultDescriptor">
> > > <xsd:attribute name="columnName" type="xsd:string"/>
> > > <xsd:attribute name="tableName" type="xsd:string"/>
> > > <xsd:attribute name="schemaName" type="xsd:string"/>
> > > <xsd:attribute name="columnType" type="xsd:string"/>
> > > </xsd:complexType>
> > >
> > > So, you are suggesting to add a new attribute,
> > > <xsd:attribute name="columnIdx" type="xsd:int"/>
> > > to this?
> > >
> > > Regards,
> > > Amita
> > >
> > > On 7/12/07, Adriano Crestani <ad...@apache.org> wrote:
> > > >
> > > > Yes, Amita, I agree with you there must be a way to define the
> > > > ResultDescriptor when the user create the command using
> > createCommand
> > > > method. But instead of define it in a sequence, it could be defined
> > > > relating
> > > > the ResultDescriptor with a column index.
> > > >
> > > > However, the problem the user came up on JIRA-1355 has nothing to do
> > > with
> > > > the way the sql query is created, but with the non previously
> > knowledge
> > > of
> > > > what the query may return. For example, can you tell me what the
> > follow
> > > > sql
> > > > return?
> > > >
> > > > "select * from company"
> > > >
> > > > I see two cases where the user cannot foreseen the company
> > attributes
> > > > retrieved on this query:
> > > >
> > > > 1 - the company attributes may change on future.
> > > > 2 - defining the company attributes is not on his charge.
> > > >
> > > > On the first case, the user can manually redefine the company
> > attributes
> > > > on
> > > > ResultDescriptor every time it changes. But on the second one, the
> > user
> > > > might not be able to know when it changes.
> > > >
> > > > The only way to overcome this problem is to leave it with JDBC
> > metadata.
> > > > Unfortunately, Oracle JDBC Driver does not provide all necessary
> > > metadata
> > > > that DAS needs : (
> > > >
> > > > Regards,
> > > > Adriano Crestani
> > > >
> > > > On 7/12/07, Amita Vadhavkar < amita.vadhavkar@gmail.com> wrote:
> > > > >
> > > > > Hi,
> > > > > Recently there came up a requirement from user (ref. JIRA-1355),
> > when
> > > > the
> > > > > user
> > > > > was attempting DAS.createCommand(sql) in Oracle. As of today, in
> > RDB
> > > > DAS,
> > > > > user
> > > > > can specify ResultDescriptor using external Config File containing
> >
> > > > > Commands.
> > > > > But
> > > > > there is no provision for user to pass ResultDescriptor for a
> > Command,
> > > > > when
> > > > > it is
> > > > > created as above (dynamic - without Config File). As, for Oracle
> > and
> > > > some
> > > > > other
> > > > > databases, when database meta data is not sufficient, DAS requires
> > > user
> > > > to
> > > > > supply
> > > > > ResultDescriptor as a substitute. For taking care of such
> > situations,
> > > > DAS
> > > > > needs to
> > > > > expose Command.set/getResultDescriptors(List <ResultDescriptor>).
> > > > >
> > > > > One rule to be adhered when using this API will be sequencing of
> > > > > ResultDescriptors
> > > > > in the input List.The sequence in the List <ResultDescriptor> has
> > to
> > > be
> > > > in
> > > > > sync
> > > > > with the sequence of parameters in "sql". With this, I guess it
> > will
> > > be
> > > > a
> > > > > really
> > > > > useful and handy functionality, that RDB DAS needs to consider.
> > > > > Thoughts?
> > > > >
> > > > > Regards,
> > > > > Amita
> > > > >
> > > >
> > >
> >
>
>
Re: [RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Posted by Amita Vadhavkar <am...@gmail.com>.
Oops, I guess after the first maill, rest of the mails were not sent to dev
list.
Regards,
Amita
On 8/7/07, Adriano Crestani <ad...@apache.org> wrote:
>
> Yes, but I suggest the name columnIndex or just index instead of
> columnIdx.
>
> Regards,
> Adriano Crestani
>
> On 8/6/07, Amita Vadhavkar <am...@gmail.com> wrote:
> >
> > Hi Adriano,
> > Just to get it clear, at present, result descriptor defn is
> > <xsd:complexType name="ResultDescriptor">
> > <xsd:attribute name="columnName" type="xsd:string"/>
> > <xsd:attribute name="tableName" type="xsd:string"/>
> > <xsd:attribute name="schemaName" type="xsd:string"/>
> > <xsd:attribute name="columnType" type="xsd:string"/>
> > </xsd:complexType>
> >
> > So, you are suggesting to add a new attribute,
> > <xsd:attribute name="columnIdx" type="xsd:int"/>
> > to this?
> >
> > Regards,
> > Amita
> >
> > On 7/12/07, Adriano Crestani <ad...@apache.org> wrote:
> > >
> > > Yes, Amita, I agree with you there must be a way to define the
> > > ResultDescriptor when the user create the command using createCommand
> > > method. But instead of define it in a sequence, it could be defined
> > > relating
> > > the ResultDescriptor with a column index.
> > >
> > > However, the problem the user came up on JIRA-1355 has nothing to do
> > with
> > > the way the sql query is created, but with the non previously
> knowledge
> > of
> > > what the query may return. For example, can you tell me what the
> follow
> > > sql
> > > return?
> > >
> > > "select * from company"
> > >
> > > I see two cases where the user cannot foreseen the company attributes
> > > retrieved on this query:
> > >
> > > 1 - the company attributes may change on future.
> > > 2 - defining the company attributes is not on his charge.
> > >
> > > On the first case, the user can manually redefine the company
> attributes
> > > on
> > > ResultDescriptor every time it changes. But on the second one, the
> user
> > > might not be able to know when it changes.
> > >
> > > The only way to overcome this problem is to leave it with JDBC
> metadata.
> > > Unfortunately, Oracle JDBC Driver does not provide all necessary
> > metadata
> > > that DAS needs : (
> > >
> > > Regards,
> > > Adriano Crestani
> > >
> > > On 7/12/07, Amita Vadhavkar <am...@gmail.com> wrote:
> > > >
> > > > Hi,
> > > > Recently there came up a requirement from user (ref. JIRA-1355),
> when
> > > the
> > > > user
> > > > was attempting DAS.createCommand(sql) in Oracle. As of today, in RDB
> > > DAS,
> > > > user
> > > > can specify ResultDescriptor using external Config File containing
> > > > Commands.
> > > > But
> > > > there is no provision for user to pass ResultDescriptor for a
> Command,
> > > > when
> > > > it is
> > > > created as above (dynamic - without Config File). As, for Oracle and
> > > some
> > > > other
> > > > databases, when database meta data is not sufficient, DAS requires
> > user
> > > to
> > > > supply
> > > > ResultDescriptor as a substitute. For taking care of such
> situations,
> > > DAS
> > > > needs to
> > > > expose Command.set/getResultDescriptors(List <ResultDescriptor>).
> > > >
> > > > One rule to be adhered when using this API will be sequencing of
> > > > ResultDescriptors
> > > > in the input List.The sequence in the List <ResultDescriptor> has to
> > be
> > > in
> > > > sync
> > > > with the sequence of parameters in "sql". With this, I guess it will
> > be
> > > a
> > > > really
> > > > useful and handy functionality, that RDB DAS needs to consider.
> > > > Thoughts?
> > > >
> > > > Regards,
> > > > Amita
> > > >
> > >
> >
>
Re: [RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Posted by Adriano Crestani <ad...@apache.org>.
Yes, but I suggest the name columnIndex or just index instead of columnIdx.
Regards,
Adriano Crestani
On 8/6/07, Amita Vadhavkar <am...@gmail.com> wrote:
>
> Hi Adriano,
> Just to get it clear, at present, result descriptor defn is
> <xsd:complexType name="ResultDescriptor">
> <xsd:attribute name="columnName" type="xsd:string"/>
> <xsd:attribute name="tableName" type="xsd:string"/>
> <xsd:attribute name="schemaName" type="xsd:string"/>
> <xsd:attribute name="columnType" type="xsd:string"/>
> </xsd:complexType>
>
> So, you are suggesting to add a new attribute,
> <xsd:attribute name="columnIdx" type="xsd:int"/>
> to this?
>
> Regards,
> Amita
>
> On 7/12/07, Adriano Crestani <ad...@apache.org> wrote:
> >
> > Yes, Amita, I agree with you there must be a way to define the
> > ResultDescriptor when the user create the command using createCommand
> > method. But instead of define it in a sequence, it could be defined
> > relating
> > the ResultDescriptor with a column index.
> >
> > However, the problem the user came up on JIRA-1355 has nothing to do
> with
> > the way the sql query is created, but with the non previously knowledge
> of
> > what the query may return. For example, can you tell me what the follow
> > sql
> > return?
> >
> > "select * from company"
> >
> > I see two cases where the user cannot foreseen the company attributes
> > retrieved on this query:
> >
> > 1 - the company attributes may change on future.
> > 2 - defining the company attributes is not on his charge.
> >
> > On the first case, the user can manually redefine the company attributes
> > on
> > ResultDescriptor every time it changes. But on the second one, the user
> > might not be able to know when it changes.
> >
> > The only way to overcome this problem is to leave it with JDBC metadata.
> > Unfortunately, Oracle JDBC Driver does not provide all necessary
> metadata
> > that DAS needs : (
> >
> > Regards,
> > Adriano Crestani
> >
> > On 7/12/07, Amita Vadhavkar <am...@gmail.com> wrote:
> > >
> > > Hi,
> > > Recently there came up a requirement from user (ref. JIRA-1355), when
> > the
> > > user
> > > was attempting DAS.createCommand(sql) in Oracle. As of today, in RDB
> > DAS,
> > > user
> > > can specify ResultDescriptor using external Config File containing
> > > Commands.
> > > But
> > > there is no provision for user to pass ResultDescriptor for a Command,
> > > when
> > > it is
> > > created as above (dynamic - without Config File). As, for Oracle and
> > some
> > > other
> > > databases, when database meta data is not sufficient, DAS requires
> user
> > to
> > > supply
> > > ResultDescriptor as a substitute. For taking care of such situations,
> > DAS
> > > needs to
> > > expose Command.set/getResultDescriptors(List <ResultDescriptor>).
> > >
> > > One rule to be adhered when using this API will be sequencing of
> > > ResultDescriptors
> > > in the input List.The sequence in the List <ResultDescriptor> has to
> be
> > in
> > > sync
> > > with the sequence of parameters in "sql". With this, I guess it will
> be
> > a
> > > really
> > > useful and handy functionality, that RDB DAS needs to consider.
> > > Thoughts?
> > >
> > > Regards,
> > > Amita
> > >
> >
>
Re: [RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Posted by Amita Vadhavkar <am...@gmail.com>.
Hi Adriano,
Just to get it clear, at present, result descriptor defn is
<xsd:complexType name="ResultDescriptor">
<xsd:attribute name="columnName" type="xsd:string"/>
<xsd:attribute name="tableName" type="xsd:string"/>
<xsd:attribute name="schemaName" type="xsd:string"/>
<xsd:attribute name="columnType" type="xsd:string"/>
</xsd:complexType>
So, you are suggesting to add a new attribute,
<xsd:attribute name="columnIdx" type="xsd:int"/>
to this?
Regards,
Amita
On 7/12/07, Adriano Crestani <ad...@apache.org> wrote:
>
> Yes, Amita, I agree with you there must be a way to define the
> ResultDescriptor when the user create the command using createCommand
> method. But instead of define it in a sequence, it could be defined
> relating
> the ResultDescriptor with a column index.
>
> However, the problem the user came up on JIRA-1355 has nothing to do with
> the way the sql query is created, but with the non previously knowledge of
> what the query may return. For example, can you tell me what the follow
> sql
> return?
>
> "select * from company"
>
> I see two cases where the user cannot foreseen the company attributes
> retrieved on this query:
>
> 1 - the company attributes may change on future.
> 2 - defining the company attributes is not on his charge.
>
> On the first case, the user can manually redefine the company attributes
> on
> ResultDescriptor every time it changes. But on the second one, the user
> might not be able to know when it changes.
>
> The only way to overcome this problem is to leave it with JDBC metadata.
> Unfortunately, Oracle JDBC Driver does not provide all necessary metadata
> that DAS needs : (
>
> Regards,
> Adriano Crestani
>
> On 7/12/07, Amita Vadhavkar <am...@gmail.com> wrote:
> >
> > Hi,
> > Recently there came up a requirement from user (ref. JIRA-1355), when
> the
> > user
> > was attempting DAS.createCommand(sql) in Oracle. As of today, in RDB
> DAS,
> > user
> > can specify ResultDescriptor using external Config File containing
> > Commands.
> > But
> > there is no provision for user to pass ResultDescriptor for a Command,
> > when
> > it is
> > created as above (dynamic - without Config File). As, for Oracle and
> some
> > other
> > databases, when database meta data is not sufficient, DAS requires user
> to
> > supply
> > ResultDescriptor as a substitute. For taking care of such situations,
> DAS
> > needs to
> > expose Command.set/getResultDescriptors(List <ResultDescriptor>).
> >
> > One rule to be adhered when using this API will be sequencing of
> > ResultDescriptors
> > in the input List.The sequence in the List <ResultDescriptor> has to be
> in
> > sync
> > with the sequence of parameters in "sql". With this, I guess it will be
> a
> > really
> > useful and handy functionality, that RDB DAS needs to consider.
> > Thoughts?
> >
> > Regards,
> > Amita
> >
>
Re: [RDB DAS] Need to allow passing ResultDescriptor for dynamic Commands (Ref.JIRA-1355)
Posted by Adriano Crestani <ad...@apache.org>.
Yes, Amita, I agree with you there must be a way to define the
ResultDescriptor when the user create the command using createCommand
method. But instead of define it in a sequence, it could be defined relating
the ResultDescriptor with a column index.
However, the problem the user came up on JIRA-1355 has nothing to do with
the way the sql query is created, but with the non previously knowledge of
what the query may return. For example, can you tell me what the follow sql
return?
"select * from company"
I see two cases where the user cannot foreseen the company attributes
retrieved on this query:
1 - the company attributes may change on future.
2 - defining the company attributes is not on his charge.
On the first case, the user can manually redefine the company attributes on
ResultDescriptor every time it changes. But on the second one, the user
might not be able to know when it changes.
The only way to overcome this problem is to leave it with JDBC metadata.
Unfortunately, Oracle JDBC Driver does not provide all necessary metadata
that DAS needs : (
Regards,
Adriano Crestani
On 7/12/07, Amita Vadhavkar <am...@gmail.com> wrote:
>
> Hi,
> Recently there came up a requirement from user (ref. JIRA-1355), when the
> user
> was attempting DAS.createCommand(sql) in Oracle. As of today, in RDB DAS,
> user
> can specify ResultDescriptor using external Config File containing
> Commands.
> But
> there is no provision for user to pass ResultDescriptor for a Command,
> when
> it is
> created as above (dynamic - without Config File). As, for Oracle and some
> other
> databases, when database meta data is not sufficient, DAS requires user to
> supply
> ResultDescriptor as a substitute. For taking care of such situations, DAS
> needs to
> expose Command.set/getResultDescriptors(List <ResultDescriptor>).
>
> One rule to be adhered when using this API will be sequencing of
> ResultDescriptors
> in the input List.The sequence in the List <ResultDescriptor> has to be in
> sync
> with the sequence of parameters in "sql". With this, I guess it will be a
> really
> useful and handy functionality, that RDB DAS needs to consider.
> Thoughts?
>
> Regards,
> Amita
>