Module plan 

Clause ordering and index selection.

Ordering is greedy selectivity ordering: start from the most selective bound pattern and repeatedly pick the cheapest runnable clause, using per-attribute statistics from the database. Explicit clause order is the tiebreak, matching the Datomic performance model users know.

Structs

ScanChoice

How a pattern scan is keyed.

Functions

choose_index

Picks the covering index and prefix length for one pattern lookup.

order_clauses

Orders clauses for execution given the initially bound variables.