I did use an approach similar to Mike Hillyer’s methods. Basically, there is a side table that has a list of parents and children that link back to the node table, allowing me to have children with multiple parents as well as parents with multiple children, so we can group arbitrary sets of locations into “regions” or other types of groups.

Good on you for verifying obscurities! That’s hard to do, and it shows dedication that you’re intent on making sure the data is correct — very important for a DBA.

How did you deal with the schema for the tree heirarchy? Using Mike Hillyer’s method, as in here:

http://dev.mysql.com/tech-resources/articles/hierarchical-data.html

??

Yes, some stuff did get left out because this is just an example. I don’t have approval to post some real code from what I am doing.

For data massaging, I use ruby’s lambda statements in place of the :syms. So, if I can’t do just:

:olddate => :newdate

I do:

lambda {|row| do_some_stuff_to row[:olddate] } => :newdate

The library I wrote looks for this and knows what to do automatically.

Very cool idea.

How are you handling moving things like datetime to timestamp datatypes where the data needs a bit of massaging?

Keep up the good work!