Multimodal data
What is an iterator?
An iterator expands one source row into many child rows — frames, sentences, pages — and keeps a pointer back to the source.
Updated · Part of What is a view?
How it works
- The iterator reads a typed column on the base.
- Each output becomes a row of the view.
- If the source row changes, the child rows that came from it are the ones that update.
What it is not
It is not a Python for-loop you run once and dump into another store.
iterator: this, and the thing it is confused with
| This | Not this | |
|---|---|---|
| Input | One video, document, or string | A folder of files you glob |
| Output | Many rows tied to that source | A flat list with no parent |
| Refresh | On change of the source row | Rerun the loop and reload |
Where Pixeltable fits
Pixeltable iterators are arguments on a view: frame_iterator, document_splitter, string_splitter, audio_splitter.
Questions
- How does iterator work?
- The iterator reads a typed column on the base. Each output becomes a row of the view. If the source row changes, the child rows that came from it are the ones that update.
- What is iterator often confused with?
- It is not a Python for-loop you run once and dump into another store.