How to make my subreport access a different database than the main one?

1
votes

I am evaluating JasperReports and Jaspersoft Studio for using in the company I work for and I am trying to build a report that contains information from 2 different databases.

I have 2 data adapters configured.

I've my research and found out that the only way to do so is to have either a list, table or subreport in a main report, but I still can't make it work.

I took the subreport approach, I have two reports that work separately, the main one executes this query in the sample DB

select 1 from ORDERS limit 10

The subreport runs this one in a Vertica database I own:

select 1 from my_schema.my_table limit 10

Both of them, as said, run separately.

So I go to the mainreport and add a SubReport element to the ColumnHeader band, then the wizard opens:

  • In the step 1 I select the subreport from the project
  • Second step is connection. I have these options:
    • Same JDBC conection
    • Use another connection
    • Use an empty data source
    • Use a JRDatasourceExpression
    • Don't use any connection.

The first and third ones are not what I want.

I tried to set the second one, but I could not find a way to select the data adapter that I have configured.

The last one doesn't work ( I get a message saying that my_schema doesn't exists, so I think that it is still trying to access the MainReport database).

Is there anyway I can make a subreport run a query in a different database/datasource from the main report?

3
jasper-reports
Possible duplicate of Multiple queries in a single jasper document – Alex K

3 Answers

1
votes

I can summarize what I did if anyone has the same issue:

I made a proof of concept (therefore I do not have the code anymore), but I created a JRDataSource class using this tutorial and there I manually access the database and returned the rows. Then I use this as the datasource of my subreport/table. Not as nice as I wanted, but it is possible

0
votes

I guess this iReport article is also applicable to reports designed in jaspersoft studio; you just need to define the subreport connection parameter with the given expression.

0
votes

Perhaps, you can ask for help from two parameters which defined in the master report by yourself. Such as:

  1. $P{MySubreport} with type net.sf.jasperreport.engine.JasperReport;

  2. $P{MyDatasource} with type net.sf.jasperreport.engine.JRDataSource;

  3. Associate these two parameters to your subreport element respectively in attributes 'Expression' and 'Data Source Expression';

Please write your DataSource class that implements interface JRDataSource. Then, in your servlet class, put your real parameter values(JasperReport for your subreport .jasper file, and your DataSource object) into a parameters Map object, and call JasperFillManager.fillReport().