fix: reuse cursor-carried total count instead of recounting each page - #9
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IncludeCount re-ran COUNT(*) on every page even though the total was already embedded in the cursor — the cached value was only consulted when IncludeCount was false. Deep pagination with a count therefore paid a full COUNT scan per page. Now a cursor-carried count is reused as-is; COUNT(*) runs only on a cursor-less (first-of-chain) request and rides the cursor forward. Changing the query is itself a cursor-less request, so the count recomputes against the new filter there. - Centralize the count decision in TotalCountResolver (was duplicated across PaginationExecutor, KeysetQueryExecutor, KeysetProjectionExecutor) - Add PaginationCount (None sentinel + AsNullable), replacing the scattered -1 / > 0 / >= 0 count-absence handling - Document the cursor-query contract (a cursor is bound to its filter) - Bump 3.0.1 -> 3.0.2 Behavior change: with IncludeCount, later pages in a chain report the count computed on the first page rather than a freshly recomputed one. Identical for correct usage (pagination resets on filter change).
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IncludeCount re-ran COUNT(*) on every page even though the total was already embedded in the cursor. The cached value was only consulted when IncludeCount was false. Deep pagination with a count therefore paid a full COUNT scan per page.
Now a cursor-carried count is reused as-is; COUNT(*) runs only on a cursor-less (first-of-chain) request and rides the cursor forward. Changing the query is itself a cursor-less request, so the count recomputes against the new filter there.
Behavior change: with IncludeCount, later pages in a chain report the count computed on the first page rather than a freshly recomputed one.