On Sun, Jul 20, 2008 at 8:41 AM, Zeljko Vrba
On Sat, Jul 19, 2008 at 06:16:53PM +0200, Istvan Buki wrote:
Hi,
Hi, thanks for the answer!
I do not know for sure if what I'm working on is a good example for using fusion. It started as an experiment to learn more about some of the boost
libraries.
The application is a very small ETL tool which allows me to load and save data from CSV files or database tables. Each record is represented by a fusion map. Between the load and save components I can insert all kind of filters to transform the data contained in the map.
This looks like a nice examples, yes. But why do you use maps instead of vectors?
For example, I use it to implement a join component. It works more or less like a join between two database table but here the table records are represented by fusion maps and in each map there is a field used to simulate the where clause. Using the fusion::at_key<> function on a map makes that very easy. It also makes it very easy to filter out a column in a table with the fusion::erase_key<> function. Istvan