I do not see an easy solution.
On Oct 2, 9:48 am, Alexandre Andrade <alexandrema...@gmail.com> wrote:
> The case is the databases and tables are not similar.
>
> Sample case:
>
> database1: city_population_data
> database2:city_financial_data
> database3: city_sports_data
>
> while the 3 databases have SOME common information (cities), the other data
> are not common.
>
> so, in my application, I need to get cities data from diferent sources.
>
> What I think to do is create a interface like phpmyadmin, that discover and
> show the data from databases.
> But, unlike phpmyadmin, is database neutral, so it can be conected to
> postgresql and others databases.
>
> >The last 4 operations are performed at the web2py level, not the db
> >level so they may use lots memory and IO.
>
> I think to improve performance, it can use temporary tables, kind of a
> ad-hoc datawarehouse.
>
> 2010/10/2 mdipierro <mdipie...@cs.depaul.edu>
>
>
>
> > say you have two databases
>
> > db1=DAL(...)
> > db2=DAL(...)
>
> > and they contains a similar table
>
> > table1=db1.define_table('person',Field('name'))
> > table2=db2.define_table('person',table1) # same fields a table1
>
> > and you want all records from both
>
> > rows=db(table1.id>0).select()&db(table2.id>0).select()
>
> > now you can sort them by name
>
> > rows=rows.sort(lambda row: row.name)
>
> > or you can get all records without duplicates
>
> > rows=db(table1.id>0).select()|db(table2.id>0).select()
>
> > and filter those that start with 'a'
>
> > rows=rows.find(lambda row: row.name.startswith('a'))
>
> > etc.
>
> > The last 4 operations are performed at the web2py level, not the db
> > level so they may use lots memory and IO.
>
> > Massimo
>
> > On Oct 2, 3:59 am, Alexandre Andrade <alexandrema...@gmail.com> wrote:
> > > (this text was translated by google)
>
> > > Hi folks,
>
> > > I'll have to develop an application on my service that uses data from
> > > several databases.
>
> > > I'm the one time looking for a way to solve this problem within the
> > web2py
> > > and the solution is pictured below.
>
> > > I wonder if anyone has a similar situation and considerations that would
> > > have the following possible solution:
>
> > > --------------------------------------------------
> > > --------------------------------------------------
> > > ------------------
>
> > > A Universal Interface for Databases is a webservice that centralizes
> > access
> > > to all databases of a company.
>
> > > Although in most cases applications use only one database, on the whole,
> > a
> > > company has multiple databases.
>
> > > In many cases they are redundant and have duplicate information in
> > several
> > > ways.
>
> > > This means that in practice, developers or duplicate the information have
> > to
> > > create ad hoc solutions to integrate systems.
>
> > > This also requires that to generate management information, there is a
> > need
> > > to create "data warehouses" to gather all the information and extract
> > > reports.
>
> > > The purpose of the UDI is to serve as sole access to all information from
> > > all databases of the company.
>
> > > Thus, the developer connects your application to a single point, and
> > calls
> > > through the UDI all the information your application needs, as well as
> > > forward all information necessary for the UDI provide storage.
>
> > > The functions of the IDU are:
>
> > > 0. Manage the connection and communication with all legacy databases.
> > > 1. List all databases, tables and data fields available, with metadata,
> > if
> > > any
> > > 2. Allow queries that retrieve information from different databases, as
> > if
> > > they were one (least of records)
> > > 3. Let me set the mapping between the data required by the application
> > > with the various databases in a visual interface, even to the programmer.
> > > 4. Store information received as a single record distributing it in
> > > different fields of databases and tables if needed.
> > > 5. Setting a standard database application, which will store the
> > mappings
> > > of the data with all other existing databases, and to store the
> > application
> > > specific data, not available elsewhere.
> > > 6.Possuir a tool for generating reports and dashboards for nontechnical
> > > users.
>
> > > In web2py, it would be a standalone application as well as the admin, and
> > > would be used in applications as a substitute for DAL, yet remains easy
> > to
> > > generate the forms.
>
> > > The big difference, and allows using data from several sources, is that
> > the
> > > data (tables and fields) present in other banks would not need to be
> > > defined, but only mapped, and both the mapping and the possible creation
> > of
> > > tables and fields would be in a graphical interface.
>
> > > --
> > > Atenciosamente
>
> > > --
> > > =========================
> > > Alexandre Andrade
> > > Hipercenter.com
>
> --
> Atenciosamente
>
> --
> =========================
> Alexandre Andrade
> Hipercenter.com
