While describing materialized view, print `synchronous_updates` option
only if the tag is present in schema's extensions map. Previously if the
key wasn't present, the default (false) value was printed.
Fixes: #14924Closes#14928
we wait for the same condition couple lines before, so no need to
check it again using `BOOST_CHECK_EQUAL()`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14921
for faster build times and clear inter-module dependencies, we
should not #includes headers not directly used. instead, we should
only #include the headers directly used by a certain compilation
unit.
in this change, the source files under "/compaction" directories
are checked using clangd, which identifies the cases where we have
an #include which is not directly used. all the #includes identified
by clangd are removed, except for "test/lib/scylla_test_case.hh"
as it brings some command line options used by scylla tests.
see also https://clangd.llvm.org/guides/include-cleaner#unused-include-warning
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14922
In branch 5.2 we erase `dc` from `_datacenters` if there are
no more endpoints listed in `_dc_endpoints[dc]`.
This was lost unintentionally in f3d5df5448
and this commit restores that behavior, and fixes test_remove_endpoint.
Fixesscylladb/scylladb#14896
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closes#14897
The `migration_manager` service is responsible for schema convergence in
the cluster - pushing schema changes to other nodes and pulling schema
when a version mismatch is observed. However, there is also a part of
`migration_manager` that doesn't really belong there - creating
mutations for schema updates. These are the functions with `prepare_`
prefix. They don't modify any state and don't exchange any messages.
They only need to read the local database.
We take these functions out of `migration_manager` and make them
separate functions to reduce the dependency of other modules (especially
`query_processor` and CQL statements) on `migration_manager`. Since all
of these functions only need access to `storage_proxy` (or even only
`replica::database`), doing such a refactor is not complicated. We just
have to add one parameter, either `storage_proxy` or `database` and both
of them are easily accessible in the places where these functions are
called.
This refactor makes `migration_manager` unneeded in a few functions:
- `alternator::executor::create_keyspace`,
- `cql3::statements::alter_type_statement::prepare_announcement_mutations`,
- `cql3::statements::schema_altering_statement::prepare_schema_mutations`,
- `cql3::query_processor::execute_thrift_schema_command:`,
- `thrift::handler::execute_schema_command`.
We remove the `migration_manager&` parameter from all these functions.
Fixes#14339Closes#14875
* github.com:scylladb/scylladb:
cql3: query_processor::execute_thrift_schema_command: remove an unused parameter
cql3: schema_altering_statement::prepare_schema_mutations: remove an unused parameter
cql3: alter_type_statement::prepare_announcement_mutations: change parameters
alternator: executor::create_keyspace: remove an unused parameter
service: migration_manager: change the prepare_ methods to functions
This change makes tablet load balancing more efficient by performing
migrations independently for different tablets, and making new load
balancing plans concurrently with active migrations.
The migration track is interrupted by pending topology change operations.
The coordinator executes the load balancer on edges of tablet state
machine transitions. This allows new migrations to be started as soon
as tablets finish streaming.
The load balancer is also continuously invoked as long as it produces
a non-empty plan. This is in order to saturate the cluster with
streaming. A single make_plan() call is still not saturating, due
to the way algorithm is implemented.
Overload of shards is limited by the fact that load balancer algorithm tracks
streaming concurrency on both source and target shards of active
migrations and takes concurrency limit into account when producing new
migrations.
Closes#14851
* github.com:scylladb/scylladb:
tablets: load_balancer: Remove double logging
tests: tablets: Check that load balancing is interrupted by topology change
tests: tablets: Add test for load balancing with active migrations
tablets: Balance tablets concurrently with active migrations
storage_service, tablets: Extract generate_migration_updates()
storage_service, tablets: Move get_leaving_replica() to tablets.cc
locator: tablets: Move std::hash definition earlier
storage_service: Advance tablets independently
topology_coordinator: Fix missed notification on abort
tablets: Add formatter for tablet_migration_info
Maps related to column families in database are extracted
to a column_families_data class. Access to them is possible only
through methods. All methods which may preempt hold rwlock
in relevant mode, so that the iterators can't become invalid.
Fixes: #13290Closes#13349
* github.com:scylladb/scylladb:
replica: make tables_metadata's attributes private
replica: add methods to get a filtered copy of tables map
replica: add methods to check if given table exists
replica: add methods to get table or table id
replica: api: return table_id instead of const table_id&
replica: iterate safely over tables related maps
replica: pass tables_metadata to phased_barrier_top_10_counts
replica: add methods to safely add and remove table
replica: wrap column families related maps into tables_metadata
replica: futurize database::add_column_family and database::remove
There are three methods in system_keyspace namespace that run queries over `system.scylla_table_schema_history` table. For that they use qctx which's not nice.
Fortunately, all the callers already have the system_keyspace& local variable or argument they can pass to those methods. Since the accessed table belongs to system keyspace, the latter declares the querying methods as "friends" to let them get private `query_processor& _qp` member
Closes#14876
* github.com:scylladb/scylladb:
schema_tables: Extract query_processor from system_keyspace for querying
schema_tables: Add system_keyspace& argument to ..._column_mapping() calls
migration_manager: Add system_keyspace argument to get_schema_mapping()
It is possible that topology will contain nodes that are no longer normal token owners, so they don't need to be sync'ed with.
Fixes scylladb/scylladb#14793
Closes#14798
* github.com:scylladb/scylladb:
storage_service: refresh_sync_nodes: restrict to reachable token owners
storage_service: refresh_sync_nodes: fix log message
locator: topology: node::state: make fine grained
Currently the node::state is coarse grained
so one cannot distinguish between e.g. a leaving
node due to decommission (where the node is used
for reading) vs. due to remove node (where the
node is not used for reading).
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
before this change, after triggering the compaction,
compaction_manager_basic_test waits until the triggered compaction
completes. but since the regular compaction is run in a loop which
does not stop until either the daemon is stopping, or there is no
more sstables to be compacted, or the compaction is disabled.
but we only get the input sstables for compaction after swiching
to the "pending" state, and acquiring the read lock of the
compaction_state, and acquiring the read lock is implemented as
an coroutine, so there is chance that coroutine is suspended,
and the execution switches to the test. in this case, the test
will find that even after the triggered compaction completes,
there are still one or more pending compactions. hence the test
fails.
to address this problem, instead of just waiting for the compaction
to complete, we also wait until the number of pending compaction tasks
is 0. so that even if the test manages to sneak into the time window,
it won't proceed and starting check the compaction manager's stats.
Fixes#14865
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14889
We add a special mode of load balancing, enabled through error
injection, which causes it to continuously generate plans. This
should keep the topology coordinator continuously in the tablet
migration track.
We enable this mode in test_tablets.py:test_bootstrap before
bootstrapping nodes to see that bootstrap request interrupts
tablet migration track. If this would not be the case, the
test will hang.
Currently, streaming and repair processes and sends data as-is. This is wasteful: streaming might be sending data which is expired or covered by tombstones, taking up valuable bandwidth and processing time. Repair additionally could be exposed to artificial differences, due to different nodes being in different states of compactness.
This PR adds opt-in compaction to `make_streaming_reader()`, then opts in all users. The main difference being in how these choose the current compaction time to use:
* Load'n'stream and streaming uses the current time on the local node.
* Repair uses a centrally chosen compaction time, generated on the repair master and propagated to al repair followers. This is to ensure all repair participants work with the exact state of compactness.
Importantly, this compaction does *not* purge tombstones (tombstone GC is disabled completely).
Fixes: https://github.com/scylladb/scylladb/issues/3561Closes#14756
* github.com:scylladb/scylladb:
replica: make_[multishard_]streaming_reader(): make compaction_time mandatory
repair/row_level: opt in to compacting the stream
streaming: opt-in to compacting the stream
sstables_loader: opt-in for compacting the stream
replica/table: add optional compacting to make_multishard_streaming_reader()
replica/table: add optional compacting to make_streaming_reader()
db/config: add config item for enabling compaction for streaming and repair
repair: log the error which caused the repair to fail
readers: compacting_reader: use compact_mutation_state::abandon_current_partition()
mutation/mutation_compactor: allow user to abandon current partition
The callers all have local sys_ks argument:
- merge_tables_and_views()
- service::get_column_mapping()
- database::parse_system_tables()
And a test that can get it from cql_test_env.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
compaction_manager_basic_test checks the stats of compaction_manager to
verify that there are no ongoing or pending compactions after the triggering
the compaction and waiting for its completion. but in #14865, there are
still active compaction(s) after the compaction_manager's stats shows there
is at least one task completed.
to understand this issue better, let's use `BOOST_CHECK_EQUAL()` instead
of `BOOST_REQUIRE()`, so that the test does not error out when the check
fails, and we can have better understanding of the status when the test
fails.
Refs #14865
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14872
The migration_manager service is responsible for schema convergence
in the cluster - pushing schema changes to other nodes and pulling
schema when a version mismatch is observed. However, there is also
a part of migration_manager that doesn't really belong there -
creating mutations for schema updates. These are the functions with
prepare_ prefix. They don't modify any state and don't exchange any
messages. They only need to read the local database.
We take these functions out of migration_manager and make them
separate functions to reduce the dependency of other modules
(especially query_processor and CQL statements) on
migration_manager. Since all of these functions only need access
to storage_proxy (or even only replica::database), doing such a
refactor is not complicated. We just have to add one parameter,
either storage_proxy or database and both of them are easily
accessible in the places where these functions are called.
Schema digest is calculated by querying for mutations of all schema
tables, then compacting them so that all tombstones in them are
dropped. However, even if the mutation becomes empty after compaction,
we still feed its partition key. If the same mutations were compacted
prior to the query, because the tombstones expire, we won't get any
mutation at all and won't feed the partition key. So schema digest
will change once an empty partition of some schema table is compacted
away.
Tombstones expire 7 days after schema change which introduces them. If
one of the nodes is restarted after that, it will compute a different
table schema digest on boot. This may cause performance problems. When
sending a request from coordinator to replica, the replica needs
schema_ptr of exact schema version request by the coordinator. If it
doesn't know that version, it will request it from the coordinator and
perform a full schema merge. This adds latency to every such request.
Schema versions which are not referenced are currently kept in cache
for only 1 second, so if request flow has low-enough rate, this
situation results in perpetual schema pulls.
After ae8d2a550d (5.2.0), it is more liekly to
run into this situation, because table creation generates tombstones
for all schema tables relevant to the table, even the ones which
will be otherwise empty for the new table (e.g. computed_columns).
This change inroduces a cluster feature which when enabled will change
digest calculation to be insensitive to expiry by ignoring empty
partitions in digest calculation. When the feature is enabled,
schema_ptrs are reloaded so that the window of discrepancy during
transition is short and no rolling restart is required.
A similar problem was fixed for per-node digest calculation in
c2ba94dc39e4add9db213751295fb17b95e6b962. Per-table digest calculation
was not fixed at that time because we didn't persist enabled features
and they were not enabled early-enough on boot for us to depend on
them in digest calculation. Now they are enabled before non-system
tables are loaded so digest calculation can rely on cluster features.
Fixes#4485.
Manually tested using ccm on cluster upgrade scenarios and node restarts.
Closes#14441
* github.com:scylladb/scylladb:
test: schema_change_test: Verify digests also with TABLE_DIGEST_INSENSITIVE_TO_EXPIRY enabled
schema_mutations, migration_manager: Ignore empty partitions in per-table digest
migration_manager, schema_tables: Implement migration_manager::reload_schema()
schema_tables: Avoid crashing when table selector has only one kind of tables
when we convert timestamp into string it must look like: '2017-12-27T11:57:42.500Z'
it concerns any conversion except JSON timestamp format
JSON string has space as time separator and must look like: '2017-12-27 11:57:42.500Z'
both formats always contain milliseconds and timezone specification
Fixes#14518Fixes#7997Closes#14726
Using a centrally generated compaction-time, generated on the repair
master and propagated to all repair followers. For repair it is
imperative that all participants use the exact same compaction time,
otherwise there can be artificial differences between participants,
generating unnecessary repair activity.
If a repair follower doesn't get a compaction-time from the repair
master, it uses a locally generated one. This is no worse than the
previous state of each node being on some undefined state of compaction.
Doing to make_multishard_streaming_reader() what the previous commit did
to make_streaming_reader(). In fact, the new compaction_time parameter
is simply forwarded to the make_streaming_reader() on the shard readers.
Call sites are updated, but none opt in just yet.
It was found that cached_file dtor can hit the following assert
after OOM
cached_file_test: utils/cached_file.hh:379: cached_file::~cached_file(): Assertion _cache.empty()' failed.`
cached_file's dtor iterates through all entries and evict those
that are linked to LRU, under the assumption that all unused
entries were linked to LRU.
That's partially correct. get_page_ptr() may fetch more than 1
page due to read ahead, but it will only call cached_page::share()
on the first page, the one that will be consumed now.
share() is responsible for automatically placing the page into
LRU once refcount drops to zero.
If the read is aborted midway, before cached_file has a chance
to hit the 2nd page (read ahead) in cache, it will remain there
with refcount 0 and unlinked to LRU, in hope that a subsequent
read will bring it out of that state.
Our main user of cached_file is per-sstable index caching.
If the scenario above happens, and the sstable and its associated
cached_file is destroyed, before the 2nd page is hit, cached_file
will not be able to clear all the cache because some of the
pages are unused and not linked.
A page read ahead will be linked into LRU so it doesn't sit in
memory indefinitely. Also allowing for cached_file dtor to
clear all cache if some of those pages brought in advance
aren't fetched later.
A reproducer was added.
Fixes#14814.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closes#14818
Te view updating consumer uses `_buffer_size` to decide when to flush the accumulated mutations, passing them to the actual view building code. This `_buffer_size` is incremented every time a mutation fragment is consumed. This is not exact, as e.g. range tombstones are represented differently in the mutation object, than in the fragment, but it is good enough. There is one flaw however: `_buffer_size` is not incremented when consuming a partition-start fragment. This is when the mutation object is created in the mutation rebuilder. This is not a big problem when partition have many rows, but if the partitions are tiny, the error in accounting quickly becomes significant. If the partitions are empty, `_buffer_size` is not bumped at all for empty partitions, and any number of these can accumulate in the buffer. We have recently seen this causing stalls and OOM as the buffer got to immense size, only containing empty and tiny partitions.
This PR fixes this by accounting the size of the freshly created `mutation` object in `_buffer_size`, after the partition-start fragment is consumed.
Fixes: #14819Closes#14821
* github.com:scylladb/scylladb:
test/boost/view_build_test: add test_view_update_generator_buffering_with_empty_mutations
db/view/view_updating_consumer: account for the size of mutations
mutation/mutation_rebuilder*: return const mutation& from consume_new_partition()
mutation/mutation: add memory_usage()
After this series, tablet replication can handle the scenario of bootstrapping new nodes. The ownership is distributed indirectly by the means of a load-balancer which moves tablets around in the background. See docs/dev/topology-over-raft.md for details.
The implementation is by no means meant to be perfect, especially in terms of performance, and will be improved incrementally.
The load balancer will be also kicked by schema changes, so that allocation/deallocation done during table creation/drop will be rebalanced.
Tablet data is streamed using existing `range_streamer`, which is the infrastructure for "the old streaming". This will be later replaced by sstable transfer once integration of tablets with compaction groups is finished. Also, cleanup is not wired yet, also blocked by compaction group integration.
Closes#14601
* github.com:scylladb/scylladb:
tests: test_tablets: Add test for bootstraping a node
storage_service: topology_coordinator: Implement tablet migration state machine
tablets: Introduce tablet_mutation_builder
service: tablet_allocator: Introduce tablet load balancer
tablets: Introduce tablet_map::for_each_tablet()
topology: Introduce get_node()
token_metadata: Add non-const getter of tablet_metadata
storage_service: Notify topology state machine after applying schema change
storage_service: Implement stream_tablet RPC
tablets: Introduce global_tablet_id
stream_transfer_task, multishard_writer: Work with table sharder
tablets: Turn tablet_id into a struct
db: Do not create per-keyspace erm for tablet-based tables
tablets: effective_replication_map: Take transition stage into account when computing replicas
tablets: Store "stage" in transition info
doc: Document tablet migration state machine and load balancer
locator: erm: Make get_endpoints_for_reading() always return read replicas
storage_service: topology_coordinator: Sleep on failure between retries
storage_service: topology_coordinator: Simplify coordinator loop
main: Require experimental raft to enable tablets
A test reproducing #14819, that is, the view update builder not flushing
the buffer when only empty partitions are consumed (with only a
tombstone in them).
The method is called by db::truncate_table_on_all_shards(), its call-chain, in turn, starts from
- proxy::remote::handle_truncate()
- schema_tables::merge_schema()
- legacy_schema_migrator
- tests
All of the above are easy to get system_keyspace reference from. This, in turn, allows making the method non-static and use query_processor reference from system_keyspace object in stead of global qctx
Closes#14778
* github.com:scylladb/scylladb:
system_keyspace: Make save_truncation_record() non-static
code: Pass sharded<db::system_keyspace>& to database::truncate()
db: Add sharded<system_keyspace>& to legacy_schema_migrator
It's needed to implement tablet migration. It stores the current step
of tablet migration state machine. The state machine will be advanced
by the topology change coordinator.
See the "Tablet migration" section of topology-over-raft.md
Just a simplification.
Drop the test case from token_metadata which creates pending endpoints
without normal tokens. It fails after this change with exception:
"sorted_tokens is empty in first_token_index!" thrown from
token_metadata::first_token_index(), which is used when calculating
normal endpoints. This test case is not valid, first node inserts
its tokens as normal without going through bootstrap procedure.
As a preparation for ensuring access safety for column families
related maps, add tables_metadata, access to members of which
would be protected by rwlock.
in this series, we use different table names in simple_backlog_controller_test. this test is a test exercising sstables compaction strategies. and it creates and keeps multiple tables in a single test session. but we are going to add metrics on per-table basis, and will use the table's ks and cf as the counter's labels. as the metrics subsystem does not allow multiple counters to share the same label. the test will fail when the metrics are being added.
to address this problem, in this change
1. a new ctor is added for `simple_schema`, so we can create `simple_schema` with different names
2. use the new ctor in simple_backlog_controller_test
Fixes#14767Closes#14783
* github.com:scylladb/scylladb:
test: use different table names in simple_backlog_controller_test
test/lib/simple_schema: add ctor for customizing ks.cf
test/lib/simple_schema: do not hardwire ks.cf
If semaphore mismatch occurs, check whether both semaphores belong
to user. If so, log a warning, log a `querier_cache_scheduling_group_mismatches` stat and drop cached reader instead of throwing an error.
Until now, semaphore mismatch was only checked in multi-partition queries. The PR pushes the check to `querier_cache` and perform it on all `lookup_*_querier` methods.
The mismatch can happen if user's scheduling group changed during
a query. We don't want to throw an error then, but drop and reset
cached reader.
This patch doesn't solve a problem with mismatched semaphores because of changes in service levels/scheduling groups but only mitigate it.
Refers: https://github.com/scylladb/scylla-enterprise/issues/3182
Refers: https://github.com/scylladb/scylla-enterprise/issues/3050Closes: #14770Closes#14736
* github.com:scylladb/scylladb:
querier_cache: add stats of scheduling group mismatches
querier_cache: check semaphore mismatch during querier lookup
querier_cache: add reference to `replica::database::is_user_semaphore()`
replica:database: add method to determine if semaphore is user one
Previously semaphore mismatch was checked only in multi-partition
queries and if happened, an internal error was thrown.
This commit pushed the check down to `querier_cache`, so each
`lookup_*_querier` method will check for the mismatch.
What's more, if semaphore mismatch occurs, check whether both semaphores belong
to user. If so, log a warning and drop cached reader instead of
throwing an error.
The mismatch can happen if user's scheduling group changed during
a query. We don't want to throw an error then, but drop and reset
cached reader.
in `simple_backlog_controller_test`, we need to have multiple tables
at the same time. but the default constructor of `simple_schema` always
creates schema with the table name of "ks.cf". we are going to have
a per-table metrics. and the new metric group will use the table name
as its counter labels, so we need to either disable this per-table
metrics or use a different table name for each table.
as in real world, we don't have multiple tables at the same time. it
would be better to stop reusing the same table name in a single test
session. so, in this change, we use a random cf_name for each of
the created table.
Fixes#14767
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
The arguments goes via the db::(drop|truncate)_table_on_all_shards()
pair of calls that start from
- storage_proxy::remote: has its sys.ks reference already
- schema_tables::merge_schema: has sys.ks argument already
- legacy_schema_migrator: the reference was added by previous patch
- tests: run in cql_test_env with sys.ks on board
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The mutation compactor has a validator which it uses to validate the stream of mutation fragments that passes through it. This validator is supposed to validate the stream as it enters the compactor, as opposed to its compacted form (output). This was true for most fragment kinds except range tombstones, as purged range tombstones were not visible to
the validator for the most part.
This mistake was introduced by https://github.com/scylladb/scylladb/commite2c9cdb576, which itself was a flawed attempt at fixing an error seen because purged tombstones were not terminated by the compactor.
This patch corrects this mistake by fixing the above problem properly: on page-cut, if the validator has an active tombstone, a closing tombstone is generated for it, to avoid the false-positive error. With this, range tombstones can be validated again as they come in.
The existing unit test checking the validation in the compactor is greatly expanded to check all (I hope) different validation scenarios.
Closes#13817
* github.com:scylladb/scylladb:
test/mutation_test: test_compactor_validator_sanity_test
mutation/mutation_compactor: fix indentation
mutation/mutation_compactor: validate the input stream
mutation: mutation_fragment_stream_validating_filter: add accessor to underlying validator
readers: reader-from-fragment: don't modify stream when created without range
let's use RAII to tear down the client and the input file, so we can
always perform the cleanups even if the test throws.
Closes#14765
* github.com:scylladb/scylladb:
s3/test: use seastar::deferred() to perform cleanup
s3/test: close using deferred_close()
The "fix" is straightforward -- callers of system_keyspace::*paxos* methods need to get system keyspace from somewhere. This time the only caller is storage_proxy::remote that can have system keyspace via direct dependency reference.
Closes#14758
* github.com:scylladb/scylladb:
db/system_keyspace: Move and use qctx::execute_cql_with_timeout()
db/system_keyspace: Make paxos methods non-static
service/paxos: Add db::system_keyspace& argument to some methods
test: Optionally initialize proxy remote for cql_test_env
proxy/remote: Keep sharded<db::system_keyspace>& dependency
Task manager tasks covering reshard compaction.
Reattempt on https://github.com/scylladb/scylladb/pull/14044. Bugfix for https://github.com/scylladb/scylladb/issues/14618 is squashed with 95191f4.
Regression test added.
Closes#14739
* github.com:scylladb/scylladb:
test: add test for resharding with non-empty owned_ranges_ptr
test: extend test_compaction_task.py to test resharding compaction
compaction: add shard_reshard_sstables_compaction_task_impl
compaction: invoke resharding on sharded database
compaction: move run_resharding_jobs into reshard_sstables_compaction_task_impl::run()
compaction: add reshard_sstables_compaction_task_impl
compaction: create resharding_compaction_task_impl
Greatly expand this test to check that the compactor validates the input
stream properly.
The test is renamed (the _sanity_test suffix is removed) to reflect the
expanded scope.
Commit f5e3b8df6d introduced an optimization for
as_mutation_source_excluding_staging() and added a test that
verifies correctness of single key and range reads based
on supplied predicates. This new test aims to improve the
coverage by testing directly both table::as_mutation_source()
and as_mutation_source_excluding_staging(), therefore
guaranteeing that both supply the correct predicate to
sstable set.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closes#14763
let's use RAII to remove the object use as a fixture, so we don't
leave some object in the bucket for testing. this might interfere
with other tests which share the same minio server with the test
which fails to do its clean up if an exception is thrown.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
let's use RAII to tear down the client and the input file, so we can
always perform the cleanups even if the test throws.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
`expression`'s default constructor is dangerous as an it can leak
into computations and generate surprising results. Fix that by
removing the default constructor.
This is made somewhat difficult by the parser generator's reliance
on default construction, and we need to expand our workaround
(`uninitialized<>`) capabilities to do so.
We also remove some incidental uses of default-constructed expressions.
Closes#14706
* github.com:scylladb/scylladb:
cql3: expr: make expression non-default-constructible
cql3: grammar: don't default-construct expressions
cql3: grammar: improve uninitialized<> flexibility
cql3: grammar: adjust uninitialized<> wrapper
test: expr_test: don't invoke expression's default constructor
cql3: statement_restrictions: explicitly initialize expressions in index match code
cql3: statement_restrictions: explicitly intitialize some expression fields
cql3: statement_restrictions: avoid expression's default constructor when classifying restrictions
cql3: expr: prepare_expression: avoid default-constructed expression
cql3: broadcast_tables: prepare new_value without relying on expression default constructor
Some test cases that use cql_test_env involve paxos state updates. Since
this update is becoming via proxy->remote->system_keyspace those test
cases need cql_test_env to initialize the remote part of the proxy too
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>