Evaluation Criteria
The decision to use deeply embedded structures (JSON object and MAP) in a single document or opt for a flat model instead depends on your specific requirements, relationships between data, and tolerance for certain tradeoffs.
For information about the JSON object that functions as a REGISTER and the MAP data type, see Data Types.
The flat model is a simple, non‑embedded structure in which you spread your data across multiple separate documents. For more information, see Relationships > Good Pattern: Flat Models.
When assessing whether to embed a nested structure in a document or distribute the data across multiple smaller documents, refer to the following criteria to guide you:
The following table provides criteria for the levels of complexity in your data model:
Criteria | Model |
|---|---|
You have a clear relationship between data items stored together in a collection. | Embedded |
Your data items are relatively simple and do not need a strong relationship. | Flat |
The following table provides criteria for the speed and efficiency of read and write operations:
Criteria | Model |
|---|---|
You frequently retrieve or update the embedded items —encapsulated key-value pairs — together. | Embedded MAP |
You frequently access or modify only certain parts of the data. | Flat |
The following table provides criteria for the potential size of the embedded MAP:
Syncing large documents can significantly impact network performance:
Caution is advised when handling large binary data, such as a high-resolution image or video exceeding 50 megapixels; a deeply embedded document; or a very large document.
Instead of storing files exceeding 250kb directly within a document object, carefully consider using the ATTACHMENT data type. For more information, see Data Types > ATTACHMENT.
Criteria | Model |
|---|---|
You do not anticipate the embedded MAP to become too large and potentially impact overall system performance. | Embedded |
You anticipate the embedded MAP to increase in complexity and size and therefore become difficult to manage and so large that system performance degrades. | Flat |
The following table provides criteria for the potential for concurrent edits and resulting merge conflicts:
Criteria | Model |
|---|---|
It is very likely that your end users will modify the same data items stored locally on their respective environments while internet is unavailable. | Embedded |
It is not likely that your end users will modify the same data items stored locally on their respective environments while internet is unavailable. | Flat |
The following table provides a criteria for assessing the overall structure of your documents:
Criteria | Model |
|---|---|
Your embedded MAP are relatively simple in structure and do not require maintainability over time. | Embedded |
Multiple embedded MAP are becoming deeply nested; as in you have an embedded map representing three or more levels in a hierarchy, necessitating better organization. | Flat |
The following table provides criteria for assessing how your data model may evolve over time:
Criteria | Model |
|---|---|
You anticipate that you'll add more data or expand relationships in the future. | Embedded |
You do not anticipate that you'll add more data or expand relationships in the future. | Flat |