indexing - What is the use case that makes EAVT index preferable to EATV? -

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from understand, eatv (which datomic not have) great fit as-of queries. on other hand, see no use-case eavt.

this analogous row/primary key access. docs: "the eavt index provides efficient access given entity. conceptually similar row access style in sql database, except entities can possess arbitrary attributes rather being limited predefined set of columns."

the immutable time/history side of datomic motivating use case it, in general, it's still optimized around typical database operations, e.g. looking entity's attributes , values.

update:

datomic stores datoms (in segments) in index tree. navigate particular e's segment using tree , retrieve datoms e in segment, eavt datoms. comment, believe you're thinking of navigation of more b-tree structures @ each step, incorrect. once you've navigated e, accessing leaf segment of (sorted) datoms.


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