Creating Dynamic Sizing Charts with Pentaho Report Designer.

Another tutorial from Prashant.
In this one he explain us the Pentaho Report Designer’s (PRD) charting capability.
Read it.

Pentaho Report Designer and Excel Data Sources - Analyse This

In this tutorial Prashant show us that Pentaho Report Designer (PRD) can be  an alternative to Mircosoft Excel, Access or other big BI vendors.
read it.

Intercept null value on a query

These last days working to create a Pentaho report with openERP data, I came across a serious problem:
if a query return a null value arithmetic operations are in error. The question was how to intercept the null value, surfing on Google I found this

SELECT IFNULL (1,0) this query return 1
SELECT IFNULL(null, 0) this query return 0

Fine my problem was solved NO!!  openERP use postgresql and postgresql doesn't support IFNULL
Again surfing on Google and I found COALESCE
The postgresql manual say:

The COALESCE function returns the first arguments of ITS THAT IS NOT NULL. Returned is null only if all arguments are null. Often it is used to substitute a default value for null values 

Finally my problem was solved my query now  is something like this
SELECT COALESCE(sum(aal.amount * -1) , 0) FROM account_analytic_line AS aal WHERE (aal.account_id=83) and aal.journal_id = 3

Rinaldo

Creating Cascade Parameters with Pentaho Report Designer 3.5.

New from Prashant :

Cascade parameters provide a way of managing large amounts of data in reports. You can define a set of related parameters so that the list of values for one parameter depends on the value chosen in another parameter.

In this example I will be using the Steel Wheels sample data to create a report which will display a list of customers using two parameters: a drop down parameter which will contain a distinct list of countries which will then filter another drop down parameter which contains cities which belong to the country.
Read the rest on the Prashant site