Module 3 · Lecture 3.3
Entities
Why classes need entities, how syncing creates them, and the sync policies that protect your edits.
Entities are the specific instances of a class: for a class city that would be London, Berlin and Tokyo. Without them Veezoo can still aggregate per region, but a question that names a value, like "show all line items from the West", has nothing in the graph to resolve "the West" against.
This lecture syncs the entities of the Region class, uses them in autocomplete and filters, renames one, and then looks at how entities stay up to date: manual and scheduled syncs, and the sync policy that decides what a sync may touch.
Key points
- Entities: the unique values of a class. With them "the West" resolves to a region, and without them that word is not in the graph at all.
- Syncing: one click scans the column and creates an entity per distinct value. From then on Veezoo suggests them in autocomplete and offers them as filter values.
- Name and ID: every entity has an ID that is matched in the database and a name you can edit freely, so Central can become North without touching the data.
- When to sync: classes with a manageable set of values that users name in questions, even a few hundred products. Millions of orders with cryptic IDs are not worth it.
- Privacy: Veezoo normally does not store your data, but synced entities are stored, so sensitive values such as phone numbers stay out of the sync.
- Sync policies:
merge(the default) keeps your edits and only adds new values,replacerebuilds the whole entities file each sync, andignoreexcludes the class from syncing entirely. - Staying current: sync manually after new data arrives, or schedule syncs daily or hourly for specific concepts or all of them.
Check your understanding
While typing "show all line items from the West", Veezoo suggests West as a region in the autocomplete. What makes that suggestion possible?
The sync created an entity for West, so Veezoo knows it as a possible region and can offer it while you type.
You renamed the entity Central to North. Which sync policy keeps that edit while still adding new regions on the next sync?
merge, the default, leaves edited entities alone and only adds what is new, while replace rebuilds the file and loses the edit.
A hospital models patients, and the name column holds real patient names. Why should those values not be synced as entities?
Veezoo normally does not store your data, but synced entities are stored, so sensitive values stay out of the sync.