Your hierarchical data questions answered
Can I use the UNICOM Intelligence Data Model aggregation functions to do summary calculations on my hierarchical data?
You can use the
Aggregate functions that are built into the UNICOM Intelligence Data Model to aggregate your data when using the hierarchical
HDATA view as well as when you are using the flat
VDATA view.
Are the HDATA tables normalized?
The HDATA virtual tables consist of a set of hierarchical tables, each one of which has a primary key. This means that, unlike the flat VDATA table, the HDATA tables are normalized (but they are not a relational database).
Why is my XML data not automatically HDATA-enabled like my RDB data?
The view that XML CDSC returns depends on the format of the data in the XML file: if the data is stored in the VDATA format, the flat VDATA table is returned; if the data is stored in the HDATA format, the hierarchical HDATA tables is returned; and if the data is stored in both formats, both VDATA and HDATA is returned. Similarly, when writing to an XML file, XML CDSC writes the data in either VDATA or HDATA format, depending on the way the data is passed to it.
This means that the data in your existing XML files will be stored in the VDATA format, because that is the way the data was passed to the CDSC when the files were created. As a result, your existing XML files will not be HDATA-enabled.
If you want to transfer hierarchical data so that you can use it in UNICOM Intelligence Reporter or UNICOM Intelligence Reporter - Survey Tabulation, use the
UNICOM Intelligence Data File CDSC.
See also