Design Applications Based on Summary/Non-Summary Data Storage
Items can contain summary or non-summary data. Non-summary data is typically rich text data that is very long text, binary data, images, and so on. Summary data (which is all non-rich text data) can appear in views and folders, whereas non-summary data can not.
When certain items are created, they are designated as summary fields by default. This saves time and space, and thus improves performance, when the view indexes are compiling (because only summary items are displayed in views) and/or when the databases are replicating (because users can select to replicate only summary information to local replicas).
When items are created programmatically in a document via the New method of ...