flat_mutation_reader_v2 was introduced in a pair of commits in 2021:
e3309322c3 "Clone flat_mutation_reader related classes into v2 variants"
08b5773c12 "Adapt flat_mutation_reader_v2 to the new version of the API"
as a replacement for flat_mutation_reader, using range_tombstone_change
instead of range_tombstone to represent represent range tombstones. See
those commits for more information.
The transition was incremental; the last use of the original
flat_mutation_reader was removed in 2022 in commit
026f8cc1e7 "db: Use mutation_partition_v2 in mvcc"
In turn, flat_mutation_reader was introduced in 2017 in commit
748205ca75 "Introduce flat_mutation_reader"
To transition from a mutation_reader that nested rows within
a partition in a separate stream, to a flat reader that streamed
partitions and rows in the same stream.
Here, we reclaim the original name and rename the awkward
flat_mutation_reader_v2 to mutation_reader.
Note that mutation_fragment_v2 remains since we still use the original
for compatibilty, sometimes.
Some notes about the transition:
- files were also renamed. In one case (flat_mutation_reader_test.cc), the
rename target already existed, so we rename to
mutation_reader_another_test.cc.
- a namespace 'mutation_reader' with two definitions existed (in
mutation_reader_fwd.hh). Its contents was folded into the mutation_reader
class. As a result, a few #includes had to be adjusted.
Closesscylladb/scylladb#19356
The DIGEST_FOR_NULL_VALUES feature was added in 21a77612b3 (2020; 4.4)
and can now be assumed to be always present. The hasher which it invoked
is removed.
transformed_cr is moved in a loop, in each iteration. This is harmless
because the variable is const and the move has no effect, yet it is
confusing to readers and triggers false positives in clang-tidy
(moved-from object reused). Remove it.
Fixes: #18322Closesscylladb/scylladb#18348
This patch changes get_unlimited_query_max_result_size():
* Also set the page-size field, not just the soft/hard limits
* Renames it to get_query_max_result_size()
* Update callers, specifically storage_proxy::get_max_result_size(),
which now has a much simpler common return path and has to drop the
page size on one rare return path.
This is a purely mechanical change, no behaviour is changed.
C++20 introduced a new overload of std::stringstream::str()
that is selected when the mentioned member function is called
on r-value.
The new overload returns a string, that is move-constructed
from the underlying string instead of being copy-constructed.
This change applies std::move() on stringstream objects before
calling str() member function to avoid copying of the underlying
buffer.
Moreover, it introduces usage of std::stringstream::view() when
checking if the stream contains some characters. It skips another
copy of the underlying string, because std::string_view is returned.
Signed-off-by: Patryk Wrobel <patryk.wrobel@scylladb.com>
Closesscylladb/scylladb#17084
The current read-loop fails to detect end-of-page and if the query
result buider cuts the page, it will just proceed to the next
partition. This will result in distorted query results, as the result
builder will request for the consumption to stop after each clustering
row.
To fix, check if the page was cut before moving on to the next
partition.
A unit test reproducing the bug was also added.
This reverts commit 628e6ffd33, reversing
changes made to 45ec76cfbf.
The test included with this PR is flaky and often breaks CI.
Revert while a fix is found.
Fixes: #15371
The current read-loop fails to detect end-of-page and if the query
result buider cuts the page, it will just proceed to the next
partition. This will result in distorted query results, as the result
builder will request for the consumption to stop after each clustering
row.
To fix, check if the page was cut before moving on to the next
partition.
A unit test reproducing the bug was also added.
This file contains facilities to dump the underlying mutations contained
in various mutation sources -- like memtable, cache and sstables -- and
return them as query results. This can be used with any table on the
system. The output represents the mutation fragments which make up said
mutations, and it will be generated according to a schema, which is a
transformation of the table's schema.
This file provides a method, which can be used to implement the backend
of a select-statement: it has a similar signature to regular query
methods.