special table from clock

[Martin <kleinerdrache@gmx.at>]

Hi there,

I know, this is a very special question, but I hope you have some ideas
about that.

I'd like to create a table from my org file appointments:

Table for March 2014
| Day | Kind | Eltern | Familie | km |
|-----+------+--------+---------+----|
|   1 |      |      4 |       3 | 32 |
|   2 |      |        |         |    |
|   3 |    2 |        |         |    |
|   4 |    6 |        |       4 | 32 |
|     |      |        |         |    |

This is where Day is the day of the month, Kind, Eltern, Familie are
something like categories the appt belongs to, maybe not categories but
subcategories.  km is the distance of driving for that job.  The count
below the subcategories are not hours, that are quater hours, so a
number of 4 tells me it is one hour.

At the end of the table I'd like to have it summarized per subcategory
and the km.

But I'm unsure how to store the data for that in my APPT entries:  I
could use properties (but how?)  and I would really like to use the
CLOCK entries for calculating the times.

Thanks for your Ideas,
Martin