This is just a plain move of the code from `modification_statement`
to `cas_request` without changes in the logic, which will further
help to refactor `build_cas_result_set` behavior to include a row
for each LWT statement and order rows in the order of statements
in a batch.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
This field will replace max size which is currently passed once per
established rpc connection via the CLIENT_ID verb and stored as an
auxiliary value on the client_info. For now it is unused, but we update
all sites creating a read command to pass the correct value to it. In the
next patch we will phase out the old max size and use this field to pass
max size on each verb instead.
"
This is the first stage of replacing the existing restrictions code with a new representation. It adds a new class `expression` to replace the existing class `restriction`. Lots of the old code is deleted, though not all -- that will come in subsequent stages.
Tests: unit (dev, debug restrictions_test), dtest (next-gating)
"
* dekimir-restrictions-rewrite:
cql3/restrictions: Drop dead code
cql3/restrictions: Use free functions instead of methods
cql3/restrictions: Create expression objects
cql3/restrictions: Add free functions over new classes
cql3/restrictions: Add new representation
Instead of `restriction` class methods, use the new free functions.
Specific replacement actions are listed below.
Note that class `restrictions` (plural) remains intact -- both its
methods and its type hierarchy remain intact for now.
Ensure full test coverage of the replacement code with new file
test/boost/restrictions_test.cc and some extra testcases in
test/cql/*.
Drop some existing tests because they codify buggy behaviour
(reference #6369, #6382). Drop others because they forbid relation
combinations that are now allowed (eg, mixing equality and
inequality, comparing to NULL, etc.).
Here are some specific categories of what was replaced:
- restriction::is_foo predicates are replaced by using the free
function find_if; sometimes it is used transitively (see, eg,
has_slice)
- restriction::is_multi_column is replaced by dynamic casts (recall
that the `restrictions` class hierarchy still exists)
- utility methods is_satisfied_by, is_supported_by, to_string, and
uses_function are replaced by eponymous free functions; note that
restrictions::uses_function still exists
- restriction::apply_to is replaced by free function
replace_column_def
- when checking infinite_bound_range_deletions, the has_bound is
replaced by local free function bounded_ck
- restriction::bounds and restriction::value are replaced by the more
general free function possible_lhs_values
- using free functions allows us to simplify the
multi_column_restriction and token_restriction hierarchies; their
methods merge_with and uses_function became identical in all
subclasses, so they were moved to the base class
- single_column_primary_key_restrictions<clustering_key>::needs_filtering
was changed to reuse num_prefix_columns_that_need_not_be_filtered,
which uses free functions
Fixes#5799.
Fixes#6369.
Fixes#6371.
Fixes#6372.
Fixes#6382.
Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
This patch adds a new `LWT` flag to `cql3::prepared_metadata`.
That allows clients to clearly distinguish betwen lwt and
non-lwt statements without need to execute some custom parsing
logic (e.g. parsing the prepared query with regular expressions),
which is obviously quite fragile.
The feature is meant to be further utilized by client drivers
to use primary replicas consistently when dealing with conditional
statements.
Whether to use lwt optimization flag or not is handled by negotiation
procedure between scylla server and client library via SUPPORTED/STARTUP
messages (`LWT_ADD_METADATA_MARK` extension).
Tests: unit(dev, debug), manual testing with modified scylla/gocql driver
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
This is more general than the previous `const partition_key&` and allows
for passing keys obtained from the likes of `frozen_mutation` that only
have a view of the key.
While at it also change the schema parameter from schema_ptr to const
schema&. No need to pass a shared pointer.
Both `cql3::column_condition` and `cql3::column_condition::raw`
classes are marked as `final`: it's safe to use lw_shared_ptr
instead of generic `seastar::shared_ptr`.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200428202249.82785-1-pa.solodovnikov@scylladb.com>
Rename inherited metrics cas_propose and cas_commit
to cas_accept and cas_learn respectively.
A while ago we made a decision to stick to widely accepted
terms for Paxos rounds: prepare, accept, learn. The rest
of the code is using these terms, so rename the metrics
to avoid confusion/technical debt.
While at it, rename a few internal methods and functions.
Fixes#6169
Message-Id: <20200414213537.129547-1-kostja@scylladb.com>
* Mark cql3::attributes::raw class as final
* Change every occurrence of ::shared_ptr<attributes::raw>
to std::unique_ptr<...>
* Mark all methods in cql3::attributes::raw as const
* Remove redundant "_attrs" ptr copy in insert_json_statement,
use one from raw::modification_statement
* Fix odd indentation in cql3/statements/update_statement.cc
Tests: unit-tests (dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200301223708.99883-1-pa.solodovnikov@scylladb.com>
* Pass raw::select_statement::parameters as lw_shared_ptr
* Some more const cleanups here and there
* lists,maps,sets::equals now accept const-ref to *_type_impl
instead of shared_ptr
* Remove unused `get_column_for_condition` from modification_statement.hh
* More methods now accept const-refs instead of shared_ptr
Every call site where a shared_ptr was required as an argument
has been inspected to be sure that no dangling references are
possible.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200220153204.279940-1-pa.solodovnikov@scylladb.com>
Previously we required MODIFY permissions on all materialized views in
order to modify a table. This is wrong, because the views should be
synced to the table unconditionally. For the same reason,
users *shouldn't* be granted MODIFY on views, to prevent them manually
changing (and breaking) a view.
This patch removes an explicit permissions check in
modification_statement introduced by 65535b3. It also tests that a
user can indeed modify a table they are allowed to modify, regardless
of lacking permissions on the table's views and indices.
Fixes#5205.
Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
De-pointerize cql3 code APIs further: change some call sites
to pass `schema` as const-ref instead of `shared_ptr`.
Affected functions known to be expecting always non-null
pointer to schema and don't store or pass the pointer somewhere
else, assuming it's safe to give them just a reference.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200218142338.69824-1-pa.solodovnikov@scylladb.com>
Take const schema& as a parameter of shard_of and
use it to obtain partitioner instead of calling
global_partitioner().
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
cql3 has cql_statement, parsed_statement and prepared_statement
classes, which, largely, stand for the same thing. prepared was
an alias for prepared_statement which only required an extra
tag jump in IDE and carried no meaning.
Now that we bounce lwt requests to the correct shard before calling into
storage_proxy the cross shard op accounting does not account for bounced
lwt statement. Fix that by increasing corresponding counter when
returning a "bounce" reply.
Message-Id: <20200203122011.GH26048@scylladb.com>
Add "const" attributes to `assignment_testable::test_assignment`
and `term::raw::prepare` methods. These should have been marked as
"const" even before the change but for some reason were missing
these qualifiers.
Mark other supplementary methods with "const" attributes as
necessary.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200127213215.494000-1-pa.solodovnikov@scylladb.com>
`parsed_statement::get_bound_variables` is assumed to always
return a nonnull pointer to `variable_specifications` instance.
In this case using a pointer is superfluous and can be safely
replaced by a plain reference.
Also add a default ctor and a utility method `set_bound_variables`
to the `variable_specifications` class to actually reset the
contents of the class instance.
Tests: unit(dev, debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20200120195839.164296-1-pa.solodovnikov@scylladb.com>
Merged pull request https://github.com/scylladb/scylla/pull/5567
from Calle Wilund:
Fixes#5314
Instead of tying CDC handling into cql statement objects, this patch set
moves it to storage proxy, i.e. shared code for mutating stuff. This means
we automatically handle cdc for code paths outside cql (i.e. alternator).
It also adds api handling (though initially inefficient) for batch statements.
CDC is tied into storage proxy by giving the former a ref to the latter (per
shard). Initially this is not a constructor parameter, because right now we
have chicken and egg issues here. Hopefully, Pavels refactoring of migration
manager and notifications will untie these and this relationship can become
nicer.
The actual augmentation can (as stated above) be made much more efficient.
Hopefully, the stream management refactoring will deal with expensive stream
lookup, and eventually, we can maybe coalesce pre-image selects for batches.
However, that is left as an exercise for when deemed needed.
The augmentation API has an optional return value for a "post-image handler"
to be used iff returned after mutation call is finished (and successful).
It is not yet actually invoked from storage_proxy, but it is at least in the
call chain.
LWT is much more efficient if a request is processed on a shard that owns
a token for the request. This is because otherwise the processing will
bounce to an owning shard multiple times. The patch proposes a way to
move request to correct shard before running lwt. It works by returning
an error from lwt code if a shard is incorrect one specifying the shard
the request should be moved to. The error is processed by transport code
that jumps to a correct shard and re-process incoming message there.
Instances of `variable_specifications` are passed around as
shared_ptr's, which are redundant in this case since the class
is marked as `final`. Use `lw_shared_ptr` instead since we know
for sure it's not a polymorphic pointer.
Tests: unit(debug)
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Message-Id: <20191225232853.45395-1-pa.solodovnikov@scylladb.com>
LWT is much more efficient if a request is processed on a shard that owns
a token for the request. This is because otherwise the processing will
bounce to an owning shard multiple times. The patch proposes a way to
move request to correct shard before running lwt. It works by returning
an error from lwt code if a shard is incorrect one specifying the shard
the request should be moved to. The error is processed by transport code
that jumps to a correct shard and re-process incoming message there.
cql_statement is a class representing a prepared statement in Scylla.
It is used concurrently during execution, so it is important that its
change is not changed by execution.
Add const qualifier to the execution methods family, throghout the
cql hierarchy.
Mark a few places which do mutate prepared statement state during
execution as mutable. While these are not affecting production today,
as code ages, they may become a source of latent bugs and should be
moved out of the prepared state or evaluated at prepare eventually:
cf_property_defs::_compaction_strategy_class
list_permissions_statement::_resource
permission_altering_statement::_resource
property_definitions::_properties
select_statement::_opts
Merged patch series from Juliusz Stasiewicz:
Welcome to my first PR to Scylla!
The task was intended as a warm-up ("noob") exercise; its description is
here: #4182 Sorry, I also couldn't help it and did some scouting: edited
descriptions of some metrics and shortened few annoyingly long LoC.
If CONSISTENCY is set to SERIAL or LOCAL SERIAL, all write requests must
fail according to Cassandra's documentation. However, batched writes
bypass this check. Fix this.
This patch resurrects Cassandra's code validating a consistency level
for CAS requests. Basically, it makes CAS requests use a special
function instead of validate_for_write to make error messages more
coherent.
Note, we don't need to resurrect requireNetworkTopologyStrategy as
EACH_QUORUM should work just fine for both CAS and non-CAS writes.
Looks like it is just an artefact of a rebase in the Cassandra
repository.
* 'cql-trivial-cleanup' of ssh://github.com/scylladb/scylla-dev:
cql: rename modification_statement::_sets_a_collection to _selects_a_collection
cql: rename _column_conditions to _regular_conditions
cql: remove unnecessary optional around prefetch_data
Since it contains a precise set of columns, it's more
accurate to call it a set, not a mask. Besides, the name
column_mask is already used for column options on storage
level.
This is merely to avoid confusion: we use _sets prefix to indicate that
there are operations over static/regular columns (_sets_static_columns,
_sets_regular_columns), but _sets_a_collection is set for both operations
and conditions. So let's rename it to _selects_a_collection and add some
comments.
It's weird that modification_statement has _static_conditions for
conditions on static columns and _column_conditions for conditions on
regular columns, as if conditions on static columns are not column
conditions. Let's rename _column_conditions to _regular_conditions to
avoid confusion.
This patch adds "type" label to the following CQL metrics:
inserts
updates
deletes
batches
statements_in_batches
The label is set to "cas" for conditional statements and "non-cas" for
unconditional statements.
Note, for a batch to be accounted as CAS, it is enough to have just one
conditional statement. In this case all statements within the batch are
accounted as CAS as well.
Apart from conditional statements, there may be other reading statements
in a batch, e.g. manipulating lists. We must not include rows fetched
for them into the CAS result set. For instance, the following CAS batch:
create table t(p int, c int, i int, l list<int>, primary key(p, c));
insert into t(p, c, i) values(1, 1, 1)
insert into t(p, c, i, l) values(1, 1, 1, [1, 2, 3])
begin batch
update t set i=3 where p=1 and c=1 if i=2
update t set l=l-[2] where p=1 and c=2
apply batch;
is supposed to return
[applied] | p | c | i
----------+---+---+---
False | 1 | 1 | 1
not
[applied] | p | c | i
----------+---+---+---
False | 1 | 1 | 1
False | 1 | 2 | 1
To filter out such collateral rows from the result set, let's mark rows
checked by conditional statements with a special flag.
If a CQL statement only updates static columns, i.e. has no clustering
key restrictions, we still fetch a regular row so that we can check it
against EXISTS condition. In this case we must be especially careful: we
can't simply pass the row to modification_statement::applies_to, because
it may turn out that the row has no static columns set, i.e. there's no
in fact static row in the partition. So we filter out such rows without
static columns right in cas_request::applies_to before passing them
further to modification_statement::applies_to.
Example:
create table t(p int, c int, s int static, primary key(p, c));
insert into t(p, c) values(1, 1);
insert into t(p, s) values(1, 1) if not exists;
The conditional statement must succeed in this case.
If a modification statement doesn't have a clustering column restriction
while the table has static columns, then EXISTS condition just needs to
check if there's a static row in the partition, i.e. it doesn't need to
select any regular rows. Let's treat such EXIST condition like a static
column condition so that we can ignore its clustering key range while
checking CAS conditions.
This will allow us to add helper methods and store extra info in each
row. For example, we can add a method for checking if a row has static
columns. Also, to build CAS result set, we need to differentiate rows
fetched to check conditions from those fetched for reading operations.
Using struct as row container will allow us to store this information in
each prefetched row.
Currently, we set _sets_regular_columns/_sets_static_columns flags when
adding regular/static conditions to modification_statement. We use them
in applies_only_to_static_columns() function that returns true iff
_sets_static_columns is set and _sets_regular_columns is clear. We
assume that if this function returns true then the statement only deals
with static columns and so must not have clustering key restrictions.
Usually, that's true, but there's one exception: DELETE FROM ...
statement that deletes whole rows. Technically, this statement doesn't
have any column operations, i.e. _sets_regular_columns flag is clear.
So if such a statement happens to have a static condition, we will
assume that it only applies to static columns and mistakenly raise an
error.
Example:
create table t(k int, c int, s int static, v int, primary key(k, c));
delete from t where k=1 and c=1 if s=1;
To fix this, let's not set the above mentioned flags when adding
conditions and instead check if _column_conditions array is empty in
applies_only_to_static_columns().
modification_statement::process_where_clause() assumes that both
operations and conditions has been added to the statement when it's
called: it uses this information to raise an error in case the statement
restrictions are incompatible with operations or conditions. Currently,
operations are set before this function is called, but not conditions.
This results in "Invalid restrictions on clustering columns since
the {} statement modifies only static columns" error while trying to
execute the following statements:
create table t(k int, c int, s int static, v int, primary key(k, c));
delete s from t where k=1 and c=1 if v=1;
update t set s=1 where k=1 and c=1 if v=1;
Fix this by always initializing conditions before processing WHERE
clause.
Support single-statement conditional updates and as well as batches.
This patch almost fully rewrites column_condition.cc, implementing
is_satisfied_by().
Most of the remaining complications in column_condition implementation
come from the need to properly handle frozen and multi-cell
collection in predicates - up until now it was not possible
to compare entire collection values between each other. This is further
complicated since multi-cell lists and sets are returned as maps.
We can no longer assume that the columns fetched by prefetch operation
are non-frozen collections. IF EXISTS/IF NOT EXISTS condition
fetches all columns, besides, a column may be needed to check other
condition.
When fetching the old row for LWT or to apply updates on list/columns,
we now calculate precisely the list of columns to fetch.
The primary key columns are also included in CAS batch result set,
and are thus also prefetched (the user needs them to figure out which
statements failed to apply).
The patch is cross-checked for compatibility with cassandra-3.11.4-1545-g86812fa502
but does deviate from the origin in handling of conditions on static
row cells. This is addressed in future series.
