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1953c5fa61
"
This series adds proper handling of filtering queries with LIMIT.
Previously the limit was erroneously applied before filtering,
which leads to truncated results.
To avoid that, paged filtering queries now use an enhanced pager,
which remembers how many rows dropped and uses that information
to fetch for more pages if the limit is not yet reached.
For unpaged filtering queries, paging is done internally as in case
of aggregations to avoid returning keeping huge results in memory.
Also, previously, all limited queries used the page size counted
from max(page size, limit). It's not good for filtering,
because with LIMIT 1 we would then query for rows one-by-one.
To avoid that, filtered queries ask for the whole page and the results
are truncated if need be afterwards.
Tests: unit (release)
"
* 'fix_filtering_with_limit_2' of https://github.com/psarna/scylla:
tests: add filtering with LIMIT test
tests: split filtering tests from cql_query_test
cql3: add proper handling of filtering with LIMIT
service/pager: use dropped_rows to adjust how many rows to read
service/pager: virtualize max_rows_to_fetch function
cql3: add counting dropped rows in filtering pager
(cherry picked from commit 1afda28cf3)