Strange database design
Why did you choose to give each element a section_left, section_right, and section_level field instead of a single section_parent field?
As it is now, items occasionally get put in the wrong order in the database by the software, at which point the software becomes incapable of displaying them and humans have a hard time manually fixing the database to get them to show up again.
A specific instance where I've noticed this happening is when an item in the tree is moved up in order to become the first subitem, the root element may keep a section_left of the old first subitem, causing the moved item to simply disappear.
A really great class
A really great class for show hierarchy records, it makes life a lot easier!
now i'm adding a new dynamic interface (via js) plus some new functionality. i will port back them when ready.
An open, cross-platform journaling program.
A scientific plotting package.