Adding a function declaration to expression.hh causes many
recompilations. Reduce that by:
- moving some restrictions-related definitions to
the existing expr/restrictions.hh
- moving evaluation related names to a new header
expr/evaluate.hh
- move utilities to a new header
expr/expr-utilities.hh
expression.hh contains only expression definitions and the most
basic and common helpers, like printing.
This reverts commit 562087beff.
The regressions introduced by the reverted change have been fixed.
So let's revert this revert to resurrect the
uuid_sstable_identifier_enabled support.
Fixes#10459
This PR changes the system to respect shard assignment to tablets in tablet metadata (system.tablets):
1. The tablet allocator is changed to distribute tablets evenly across shards taking into account currently allocated tablets in the system. Each tablet has equal weight. vnode load is ignored.
2. CDC subsystem was not adjusted (not supported yet)
3. sstable sharding metadata reflects tablet boundaries
5. resharding is NOT supported yet (the node will abort on boot if there is a need to reshard tablet-based tables)
6. The system is NOT prepared to handle tablet migration / topology changes in a safe way.
7. Sstable cleanup is not wired properly yet
After this PR, dht::shard_of() and schema::get_sharder() are deprecated. One should use table::shard_of() and effective_replication_map::get_sharder() instead.
To make the life easier, support was added to obtain table pointer from the schema pointer:
```
schema_ptr s;
s->table().shard_of(...)
```
Closes#13939
* github.com:scylladb/scylladb:
locator: network_topology_startegy: Allocate shards to tablets
locator: Store node shard count in topology
service: topology: Extract topology updating to a lambda
test: Move test_tablets under topology_experimental
sstables: Add trace-level logging related to shard calculation
schema: Catch incorrect uses of schema::get_sharder()
dht: Rename dht::shard_of() to dht::static_shard_of()
treewide: Replace dht::shard_of() uses with table::shard_of() / erm::shard_of()
storage_proxy: Avoid multishard reader for tablets
storage_proxy: Obtain shard from erm in the read path
db, storage_proxy: Drop mutation/frozen_mutation ::shard_of()
forward_service: Use table sharder
alternator: Use table sharder
db: multishard: Obtain sharder from erm
sstable_directory: Improve trace-level logging
db: table: Introduce shard_of() helper
db: Use table sharder in compaction
sstables: Compute sstable shards using sharder from erm when loading
sstables: Generate sharding metadata using sharder from erm when writing
test: partitioner: Test split_range_to_single_shard() on tablet-like sharder
dht: Make split_range_to_single_shard() prepared for tablet sharder
sstables: Move compute_shards_for_this_sstable() to load()
dht: Take sharder externally in splitting functions
locator: Make sharder accessible through effective_replication_map
dht: sharder: Document guarantees about mapping stability
tablets: Implement tablet sharder
tablets: Include pending replica in get_shard()
dht: sharder: Introduce next_shard()
db: token_ring_table: Filter out tablet-based keyspaces
db: schema: Attach table pointer to schema
schema_registry: Fix SIGSEGV in learn() when concurrent with get_or_load()
schema_registry: Make learn(schema_ptr) attach entry to the target schema
test: lib: cql_test_env: Expose feature_service
test: Extract throttle object to separate header
Fixes#11017
When doing writes, storage proxy creates types deriving from abstract_write_response_handler.
These are created in the various scheduling groups executing the write inducing code. They
pick up a group-local reference to the various metrics used by SP. Normally all code
using (and esp. modifying) these metrics are executed in the same scheduling group.
However, if gossip sees a node go down, it will notify listeners, which eventually
calls get_ep_stat and register_metrics.
This code (before this patch) uses _active_ scheduling group to eventually add
metrics, using a local dict as guard against double regs. If, as described above,
we're called in a different sched group than the original one however, this
can cause double registrations.
Fixed here by keeping a reference to creating scheduling group and using this, not
active one, when/if creating new metrics.
Closes#14294
Uses a simple algorihtm for allocating shards which chooses
least-loaded shard on a given node, encapsulated in load_sketch.
Takes load due to current tablet allocation into account.
Each tablet, new or allocated for other tables, is assumed to have an
equal load weight.
This is in order to prevent new incorrect uses of dht::shard_of() to
be accidentally added. Also, makes sure that all current uses are
caught by the compiler and require an explicit rename.
dht::shard_of() does not use the correct sharder for tablet-based tables.
Code which is supposed to work with all kinds of tables should use erm::get_sharder().
dht::shard_of() does not use the correct sharder for tablet-based tables.
Code which is supposed to work with all kinds of tables should use erm::get_sharder().
This is not strictly necessary, as the multishard reader will be later
avoided altogether for tablet-based tables, but it is a step towards
converting all code to use the erm->get_sharder() instead of
schema::get_sharder().
schema::get_sharder() does not use the correct sharder for
tablet-based tables. Code which is supposed to work with all kinds of
tables should obtain the sharder from erm::get_sharder().
The function currently assumes that shard assignment for subsequent
tokens is round robin, which will not be the case for tablets. This
can lead to incorrect split calculation or infinite loop.
Another assumption was that subsequent splits returned by the sharder
have distinct shards. This also doesn't hold for tablets, which may
return the same shard for subsequent tokens. This assumption was
embedded in the following line:
start_token = sharder.token_for_next_shard(end_token, shard);
If the range which starts with end_token is also owned by "shard",
token_for_next_shard() would skip over it.
We need those functions to work with tablet sharder, which is not
accessible through schema::get_sharder(). In order to propagate the
right sharder, those functions need to take it externally rather from
the schema object. The sharder will come from the
effective_replication_map attached to the table object.
Those splitting functions are used when generating sharding metadata
of an sstable. We need to keep this sharding metadata consistent with
tablet mapping to shards in order for node restart to detect that
those sstables belong to a single shard and that resharding is not
necessary. Resharding of sstables based on tablet metadata is not
implemented yet and will abort after this series.
Keeping sharding metadata accurate for tablets is only necessary until
compaction group integration is finished. After that, we can use the
sstable token range to determine the owning tablet and thus the owning
shard. Before that, we can't, because a single sstable may contain
keys from different tablets, and the whole key range may overlap with
keys which belong to other shards.
This will make it easier to access table proprties in places which
only have schema_ptr. This is in particular useful when replacing
dht::shard_of() uses with s->table().shard_of(), now that sharding is
no longer static, but table-specific.
Also, it allows us to install a guard which catches invalid uses of
schema::get_sharder() on tablet-based tables.
It will be helpful for other uses as well. For example, we can now get
rid of the static_props hack.
Currently, when two cells have the same write timestamp
and both are alive or expiring, we compare their value first,
before checking if either of them is expiring
and if both are expiring, comparing their expiration time
and ttl value to determine which of them will expire
later or was written later.
This was based on an early version of Cassandra.
However, the Cassandra implementation rightfully changed in
e225c88a65 ([CASSANDRA-14592](https://issues.apache.org/jira/browse/CASSANDRA-14592)),
where the cell expiration is considered before the cell value.
To summarize, the motivation for this change is three fold:
1. Cassandra compatibility
2. Prevent an edge case where a null value is returned by select query when an expired cell has a larger value than a cell with later expiration.
3. A generalization of the above: value-based reconciliation may cause select query to return a mixture of upserts, if multiple upserts use the same timeastamp but have different expiration times. If the cell value is considered before expiration, the select result may contain cells from different inserts, while reconciling based the expiration times will choose cells consistently from either upserts, as all cells in the respective upsert will carry the same expiration time.
Fixes#14182
Also, this series:
- updates dml documentation
- updates internal documentation
- updates and adds unit tests and cql pytest reproducing #14182Closes#14183
* github.com:scylladb/scylladb:
docs: dml: add update ordering section
cql-pytest: test_using_timestamp: add tests for rewrites using same timestamp
mutation_partition: compare_row_marker_for_merge: consider ttl in case expiry is the same
atomic_cell: compare_atomic_cell_for_merge: update and add documentation
compare_atomic_cell_for_merge: compare value last for live cells
mutation_test: test_cell_ordering: improve debuggability
Currently, when two cells have the same write timestamp
and both are alive or expiring, we compare their value first,
before checking if either of them is expiring
and if both are expiring, comparing their expiration time
and ttl value to determine which of them will expire
later or was written later.
This was changed in CASSANDRA-14592
for consistency with the preference for dead cells over live cells,
as expiring cells will become tombstones at a future time
and then they'd win over live cells with the same timestamp,
hence they should win also before expiration.
In addition, comparing the cell value before expiration
can lead to unintuitive corner cases where rewriting
a cell using the same timestamp but different TTL
may cause scylla to return the cell with null value
if it expired in the meanwhile.
Also, when multiple columns are written using two upserts
using the same write timestamp but with different expiration,
selecting cells by their value may return a mixed result
where each cell is selected individually from either upsert,
by picking the cells with the largest values for each column,
while using the expiration time to break tie will lead
to a more consistent results where a set of cell from
only one of the upserts will be selected.
Fixesscylladb/scylladb#14182
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Currently, it is hard to tell which of the many sub-cases
fail in this unit test, in case any of them fails.
This change uses logging in debug and trace level
to help with that by reproducing the error
with --logger-log-level testlog=trace
(The cases are deterministic so reproducing should not
be a problem)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Since `mvcc: make schema upgrades gentle` (51e3b9321b),
rows pointed to by the cursor can have different (older) schema
than the schema of the cursor's snapshot.
However, one place in the code wasn't updated accordingly,
causing a row to be processed with the wrong schema in the right
circumstances.
This passed through unit testing because it requires
a digest-computing cache read after a schema change,
and no test exercised this.
This series fixes the bug and adds a unit test which reproduces the issue.
Fixes#14110Closes#14305
* github.com:scylladb/scylladb:
test: boost/row_cache_test: add a reproducer for #14110
cache_flat_mutation_reader: use the correct schema in prepare_hash
mutation: mutation_cleaner: add pause()
There are tons of wrappers that help test cases make sstables for their needs. And lots of code duplication in test cases that do parts of those helpers' work on their own. This set cleans some bits of those
Closes#14280
* github.com:scylladb/scylladb:
test/utils: Generalize making memtable from vector<mutation>
test/util: Generalize make_sstable_easy()-s
test/sstable_mutation: Remove useless helper
test/sstable_mutation: Make writer config in make_sstable_mutation_source()
test/utils: De-duplicate make_sstable_containing-s
test/sstable_compaction: Remove useless one-line local lambda
test/sstable_compaction: Simplify sstable making
test/sstables*: Make sstable from vector of mutations
test/mutation_reader: Remove create_sstable() helper from test
It's excessive, test case that needs it can get storage prefix without
this fancy wrapper-helper
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#14273
Commit 4e205650 (test: Verify correctness of sstable::bytes_on_disk())
added a test to verify that sstable::bytes_on_disk() is equal to the
real size of real files. The same test case makes sense for S3-backed
sstables as well.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#14272
In preparation for converting selectors to evaluate expressions,
add support for evaluating column_mutation_attribute (representing
the WRITETIME/TTL pseudo-functions).
A unit test is added.
Fixes#12906Closes#14287
* github.com:scylladb/scylladb:
test: expr: test evaluation of column_mutation_attribute
test: lib: enhance make_evaluation_inputs() with support for ttls/timestamps
cql3: expr: evaluate() column_mutation_attribute
This reverts commit d1dc579062, reversing
changes made to 3a73048bc9.
Said commit caused regressions in dtests. We need to investigate and fix
those, but in the meanwhile let's revert this to reduce the disruption
to our workflows.
Refs: #14283
There's no way to evaluate a column_mutation_attribute via CQL
yet (the only user uses old-style cql3::selection::selector), so
we only supply a unit test.
Implement `expr:valuate()` for `expr::field_selection`.
`field_selection` is used to represent access to a struct field.
For example, with a UDT value:
```
CREATE TYPE my_type (a int, b int);
```
The expression `my_type_value.a` would be represented as a `field_selection`, which selects the field `a`.
Evaluating such an expression consists of finding the right element's value in a serialized UDT value and returning it.
Note that it's still not possible to use `field_selection` inside the `WHERE` clause. Enabling it would require changes to the grammar, as well as query planning, Current `statement_restrictions` just reacts with `on_internal_error` when it encounters a `field_selection`.
Nonetheless it's a step towards relaxing the grammar, and now it's finally possible to evaluate all kinds of prepared expressions (#12906)
Fixes: https://github.com/scylladb/scylladb/issues/12906Closes#14235
* github.com:scylladb/scylladb:
boost/expr_test: test evaluate(field_selection)
cql3/expr: fix printing of field_selection
cql3/expression: implement evaluate(field_selection)
types/user: modify idx_of_field to use bytes_view
column_identifer: add column_identifier_raw::text()
types: add read_nth_user_type_field()
types: add read_nth_tuple_element()
There are two make_sstable_mutation_source() helpers that call one
another and test cases only need one of them, so leave just one that's
in use.
Also don't pass env's tempdir to make_sstable() util call, it can get
env's tempdir on its own.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
These local helpers accept writer config which's made the same way by
callers, so the helpers can do it on their own
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The get_usable_sst() wrapper lambda is not needed, calling the
make_sstable_containing() is shorter
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There's a temporary memtable and on-stack lambda that makes the
mutation. Both are overkill, make_sstable_containing() can work on just
plan on-stack-constructed mutation
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There are many cases that want to call make_sstable_containing() with
the vector of mutations at hand. For that they apply it to a temporary
memtable, but sstable-utils can work with the mutations vector as well
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
In https://github.com/scylladb/scylladb/pull/14231 we split `storage_proxy` initialization into two phases: for local and remote parts. Here we do the same with `query_processor`. This allows performing queries for local tables early in the Scylla startup procedure, before we initialize services used for cluster communication such as `messaging_service` or `gossiper`.
Fixes: #14202
As a follow-up we will simplify `system_keyspace` initialization, making it available earlier as well.
Closes#14256
* github.com:scylladb/scylladb:
main, cql_test_env: start `query_processor` early
cql3: query_processor: split `remote` initialization step
cql3: query_processor: move `migration_manager&`, `forwarder&`, `group0_client&` to a `remote` object
cql3: query_processor: make `forwarder()` private
cql3: query_processor: make `get_group0_client()` private
cql3: strongly_consistent_modification_statement: fix indentation
cql3: query_processor: make `get_migration_manager` private
tracing: remove `qp.get_migration_manager()` calls
table_helper: remove `qp.get_migration_manager()` calls
thrift: handler: move implementation of `execute_schema_command` to `query_processor`
data_dictionary: add `get_version`
cql3: statements: schema_altering_statement: move `execute0` to `query_processor`
cql3: statements: pass `migration_manager&` explicitly to `prepare_schema_mutations`
main: add missing `supervisor::notify` message
Add a unit test which tests evaluating field selections.
Alas at the moment it's impossible to add a cql-pytest,
as the grammar and query planning doesn't handle field
selections inside the WHERE clause.
Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
CQL statements carry expressions in many contexts: the SELECT, WHERE, SET, and IF clauses, plus various attributes. Previously, each of these contexts had its own representation for an expression, and another one for the same expression but before preparation. We have been gradually moving towards a uniform representation of expressions.
This series tackles SELECT clause elements (selectors), in their unprepared phase. It's relatively simple since there are only five types of expression components (column references, writetime/ttl modifiers, function calls, casts, and field selections). Nevertheless, there isn't much commonality with previously converted expression elements so quite a lot of code is involved.
After the series, we are still left with a custom post-prepare representation of expressions. It's quite complicated since it deals with two passes, for aggregation, so it will be left for another series.
Closes#14219
* github.com:scylladb/scylladb:
cql3: seletor: drop inheritance from assignment_testable
cql3: selection: rely on prepared expressions
cql3: selection: prepare selector expressions
cql3: expr: match counter arguments to function parameters expecting bigint
cql3: expr: avoid function constant-folding if a thread is needed
cql3: add optional type annotation to assignment_testable
cql3: expr: wire unresolved_identifier to test_assignment()
cql3: expr: support preparing column_mutation_attribute
cql3: expr: support preparing SQL-style casts
cql3: expr: support preparing field_selection expressions
cql3: expr: make the two styles of cast expressions explicit
cql3: error injection functions: mark enabled_injections() as impure
cql3: eliminate dynamic_cast<selector> from functions::get()
cql3: test_assignment: pass optional schema everywhere
cql3: expr: prepare_expr(): allow aggregate functions
cql3: add checks for aggregation functions after prepare
cql3: expr: add verify_no_aggregate_functions() helper
test: add regression test for rejection of aggregates in the WHERE clause
cql3: expr: extract column_mutation_attribute_type
cql3: expr: add fmt formatter for column_mutation_attribute_kind
cql3: statements: select_statement: reuse to_selectable() computation in SELECT JSON
the invalid sstable id is the NULL of a sstable identifier. with
this concept, it would be a lot simpler to find/track the greatest
generation. the complexity is hidden in the generation_type, which
compares the a) integer-based identifiers b) uuid-based identifiers
c) invalid identitifer in different ways.
so, in this change
* the default constructor generation_type is
now public.
* we don't check for empty generation anymore when loading
SSTables or enumerating them.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
before this change, we assume that generation is always integer based.
in order to enable the UUID-based generation identifier if the related
option is set, we should populate this option down to generation generator.
because we don't have access to the cluster features in some places where
a new generation is created, a new accessor exposing feature_service from
sstable manager is added.
Fixes#10459
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
this change generalize the value of generation_type so it also
supports UUID based identifier.
* sstables/generation_type.h:
- add formatter and parse for UUID. please note, Cassandra uses
a different format for formatting the SSTable identifier. and
this formatter suits our needs as it uses underscore "_" as the
delimiter, as the file name of components uses dash "-" as the
delimiter. instead of reinventing the formatting or just use
another delimiter in the stringified UUID, we choose to use the
Cassandra's formatting.
- add accessors for accessing the type and value of generation_type
- add constructor for constructing generation_type with UUID and
string.
- use hash for placing sstables with uuid identifiers into shards
for more uniformed distrbution of tables in shards.
* replica/table.cc:
- only update the generator if the given generation contains an
integer
* test/boost:
- add a simple test to verify the generation_type is able to
parse and format
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
* seastar afe39231...99d28ff0 (16):
> file/util: Include seastar.hh
> http/exception: Use http::reply explicitly
> http/client: Include lost condition-variable.hh
> util: file: drop unnecessary include of reactor.hh
> tests: perf: add a markdown printer
> http/client: Introduce unexpected_status_error for client requests
> sharded: avoid #include <seastar/core/reactor.hh> for run_in_background()
> code: Use std::is_invocable_r_v instead of InvokeReturns
> http/client: Add ability to change pool size on the fly
> http/client: Add getters for active/idle connections counts
> http/client: Count and limit the number of connections
> http/client: Add connection->client RAII backref
> build: use the user-specified compiler when building DPDK
> build: use proper toolchain based on specified compiler
> build: only pass CMAKE_C_COMPILER when building ingredients
> build: use specified compiler when building liburing
Two changes are folded into the commit:
1. missing seastar/core/coroutine.hh include in one .cc file that
got it indirectly included before seastar reactor.hh drop from
file.hh
2. http client now returns unexpected_status_error instead of
std::runtime_error, so s3 test is updated respectively
Closes#14168
statement_restrictions: forbid IS NOT NULL on columns outside the primary key
IS NOT NULL is currently allowed only when creating materialized views.
It's used to convey that the view will not include any rows that would make the view's primary key columns NULL.
Generally materialized views allow to place restrictions on the primary key columns, but restrictions on the regular columns are forbidden. The exception was IS NOT NULL - it was allowed to write regular_col IS NOT NULL. The problem is that this restriction isn't respected, it's just silently ignored (see #10365).
Supporting IS NOT NULL on regular columns seems to be as hard as supporting any other restrictions on regular columns.
It would be a big effort, and there are some reasons why we don't support them.
For now let's forbid such restrictions, it's better to fail than be wrong silently.
Throwing a hard error would be a breaking change.
To avoid breaking existing code the reaction to an invalid IS NOT NULL restrictions is controlled by the `strict_is_not_null_in_views` flag.
This flag can have the following values:
* `true` - strict checking. Having an `IS NOT NULL` restriction on a column that doesn't belong to the view's primary key causes an error to be thrown.
* `warn` - allow invalid `IS NOT NULL` restrictions, but throw a warning. The invalid restrictions are silently ignored.
* `false` - allow invalid `IS NOT NULL` restricitons, without any warnings or errors. The invalid restrictions are silently ignored.
The default values for this flag are `warn` in `db::config` and `true` in scylla.yaml.
This way the existing clusters will have `warn` by default, so they'll get a warning if they try to create such an invalid view.
New clusters with fresh scylla.yaml will have the flag set to `true`, as scylla.yaml overwrites the default value in `db::config`.
New clusters will throw a hard error for invalid views, but in older existing clusters it will just be a warning.
This way we can maintain backwards compatibility, but still move forward by rejecting invalid queries on new clusters.
Fixes: #10365Closes#13013
* github.com:scylladb/scylladb:
boost/restriction_test: test the strict_is_not_null_in_views flag
docs/cql/mv: columns outside of view's primary key can't be restricted
cql-pytest: enable test_is_not_null_forbidden_in_filter
statement_restrictions: forbid IS NOT NULL on columns outside the primary key
schema_altering_statement: return warnings from prepare_schema_mutations()
db/config: add strict_is_not_null_in_views config option
statement_restrictions: add get_not_null_columns()
test: remove invalid IS NOT NULL restrictions from tests
Add unit tests for the strict_is_not_null_in_views flag.
This flag controls the behavior in case of an invalid
IS NOT NULL restrictions on a materialized view column.
Materialized views allow only restricting columns
that belong to the view's primary key, all other
restrictions should be rejected.
There was a bug where IS NOT NULL restrictions
weren't rejected, but simply ignored instead.
This flags controls what should happen when the user
runs a query with such an invalid IS NOT NULL restriction.
strict_is_not_null_in_views can have the following values:
* `true` - strict checking, invalid queries are rejected
* `warn` - the query is allowed, but a warning is printed
* `false` - the query is allowed, the invalid restrictions
are silently ignored.
The tests are based on the ones for strict_allow_filtering,
which reside in the lines preceding the newly added tests.
Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
In that level no io_priority_class-es exist. Instead, all the IO happens
in the context of current sched-group. File API no longer accepts prio
class argument (and makes io_intent arg mandatory to impls).
So the change consists of
- removing all usage of io_priority_class
- patching file_impl's inheritants to updated API
- priority manager goes away altogether
- IO bandwidth update is performed on respective sched group
- tune-up scylla-gdb.py io_queues command
The first change is huge and was made semi-autimatically by:
- grep io_priority_class | default_priority_class
- remove all calls, found methods' args and class' fields
Patching file_impl-s is smaller, but also mechanical:
- replace io_priority_class& argument with io_intent* one
- pass intent to lower file (if applicatble)
Dropping the priority manager is:
- git-rm .cc and .hh
- sed out all the #include-s
- fix configure.py and cmakefile
The scylla-gdb.py update is a bit hairry -- it needs to use task queues
list for IO classes names and shares, but to detect it should it checks
for the "commitlog" group is present.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#13963
Secondary index creation is asynchronous, meaning it
takes time for existing data to be reflected within
the index. However, new data added after the
index is created should appear in it immediately.
The test consisted of two parts. The first created
a series of indexes for one table, added
test data to the table, and then ran a series of checks.
In the second part, several new indexes were added to
the same table, and checks were made to make sure that
already existing data would appear in them. This
last part was flaky.
The patch just moves the index creation statements
from the second part to the first.
Fixes: #14076Closes#14090
