database.md

EduServer Database

Current database scheme:

Entities: User and Tag — users and course tags. Study Items — all objects related to educational materials: Course, Course Version, Section, Lesson, Task.

Table Study Items Relations stores all relations among Study Items and these relations look like tree below. Root is Course vertex. All subtree store course version for different plugin versions.

Tree update: A Task was created in the plugin with version n, then:

• If an update was made in the plugin with version n + 1 and version of some Study Item is changed to new, then add new child to the root(vertex Course) and go down this subtree, saving references to unchanged Tasks, Sections, Lessons and creating new ones for the changed.
• If an update was made in the plugin with version n + 1 and version of some Study Item isn't changed to new, then go down the tree and change old versions of Tasks, Sections and Lessons by new ones, saving references to old in field Parent Study Item ID.