Commit Graph

207 Commits

Author SHA1 Message Date
Mikołaj Grzebieluch
82df8a9905 raft: broadcast_tables: add compilation of cql to intermediate language
We decided to extend `cql_statement` hierarchy with `strongly_consistent_modification_statement`
and `strongly_consistent_select_statement`. Statements operating on
system.broadcast_kv_store will be compiled to these new subclasses if
BROADCAST_TABLES flag is enabled.

If the query is executed on a shard other than 0 it's bounced to that shard.
2022-09-08 15:25:36 +02:00
Botond Dénes
d1d53f1b84 query: add tombstone-limit to read-command
Propagate the tombstone-limit from coordinator to replicas, to make sure
all is using the same limit.
2022-08-10 06:01:47 +03:00
Avi Kivity
9823e75d16 cql3: grammar: make where clause return an expression
In preparation of the relaxation of the grammar to return any expression,
change the whereClause production to return an expression rather than
terms. Note that the expression is still constrained to be a conjunction
of relations, and our filtering code isn't prepared for more.

Before the patch, if the WHERE clause was optional, the grammar would
pass an empty vector of expressions (which is exactly correct). After
the patch, it would pass a default-constructed expression. Now that
happens to be an empty conjunction, which is exactly what's needed, but
it is too accidental, so the patch changes optional WHERE clauses to
explicitly generate an empty conjunction if the WHERE clause wasn't
specified.
2022-07-22 20:14:48 +03:00
Avi Kivity
a5dd588465 cql3: statement_restrictions: accept a single expression rather than a vector
Move closer to the goal of accepting a generic expression for WHERE
clause by accepting a generic expression in statement_restrictions. The
various callers will synthesize it from a vector of terms.
2022-07-22 20:14:48 +03:00
Jan Ciolek
2b7ffd57fb cql3: Return an expression in get_clustering_columns_restrctions()
get_clustering_columns_restrctions() used to return
a shared pointer to the clustering_restrictions class.

Now everything is being converted to expression,
so it should return an expression as well.

Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2022-07-19 16:02:01 +02:00
Jan Ciolek
1339ff1c79 cql3: Use expression instead of _partition_key_restrictions in the remaining code
There are still some places that use partition_key_restrictions
instead of _new_partition_key_restrictions in statement_restrictions.
Change them to use the new representation

Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2022-07-01 16:29:10 +02:00
Jan Ciolek
de99c0a0fa cql3: Replace partition_key_restrictions->size()
Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2022-07-01 16:29:10 +02:00
Jan Ciolek
e37ddd5b89 cql3: Remove single_column_restriction class
Now that all uses of this class have been
replaced by the generic restriction
the class is not used anywhere and can be removed.

Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2022-07-01 15:53:19 +02:00
Piotr Dulikowski
e6beab3106 storage_proxy: add allow rate limit flag to mutate/mutate_result
Now, mutate/mutate_result accept a flag which decides whether the write
should be rate limited or not.

The new parameter is mandatory and all call sites were updated.
2022-06-22 20:16:49 +02:00
Avi Kivity
4f7cbbb54c cql3: column_condition: rename column member
Prefix with underscore as a data member.
2022-06-02 13:09:54 +03:00
cvybhu
51cdbdeacb cql3: Make parser output expression for relations
Parser used to output the where clause as a vector of relations,
but now we can change it to a vector of expressions.

Cql.g needs to be modified to output expressions instead
of relations.

The WHERE clause is kept in a few places in the code that
need to be changed to vector<expression>.

Finally relation->to_restriction is replaced by expr::to_restriction
and the expressions are converted to restrictions where required.

The relation class isn't used anywhere now and can be removed.

Signed-off-by: cvybhu <jan.ciolek@scylladb.com>
2022-05-16 18:17:58 +02:00
Avi Kivity
5937b1fa23 treewide: remove empty comments in top-of-files
After fcb8d040 ("treewide: use Software Package Data Exchange
(SPDX) license identifiers"), many dual-licensed files were
left with empty comments on top. Remove them to avoid visual
noise.

Closes #10562
2022-05-13 07:11:58 +02:00
Eliran Sinvani
bf50dbd35b cql3 statements: Change dependency test API to express better it's
purpose

Cql statements used to have two API functions, depends_on_keyspace and
depends_on_column_family. The former, took as a parameter only a table
name, which makes no sense. There could be multiple tables with the same
name each in a different keyspace and it doesn't make sense to
generalize the test - i.e to ask "Does a statement depend on any table
named XXX?"
In this change we unify the two calls to one - depends on that takes a
keyspace name and optionally also a table name, that way every logical
dependency tests that makes sense is supported by a single API call.
2022-02-27 11:48:03 +02:00
Piotr Dulikowski
2572104dfe modification_statement: propagate failed result through result_message::exception
Modifies the modification_statement code so that is converts failed
`result<>` into a `result_message::exception` without involving the C++
exception runtime.
2022-02-08 11:08:42 +01:00
Piotr Dulikowski
4c1eae7600 storage_proxy: change mutate_with_triggers to return future<result<>>
Changes the interface of `mutate_with_triggers` so that it returns
`future<result<>>` instead of `future<>`. No intermediate
`mutate_with_triggers_result` method is introduced because all call
sites will be changed in this PR so that they properly handle failed
`result<>`s with exceptions-as-values.
2022-02-08 11:08:42 +01:00
Avi Kivity
fcb8d040e8 treewide: use Software Package Data Exchange (SPDX) license identifiers
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.

Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.

The changes we applied mechanically with a script, except to
licenses/README.md.

Closes #9937
2022-01-18 12:15:18 +01:00
Pavel Emelyanov
00de5f4876 validation: Make validate_column_family use data_dictionary::database
And instantly convert the validate_keyspace() as it's not called
from anywhere but the validate_column_family().

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2022-01-14 13:00:53 +03:00
Pavel Emelyanov
b6bc7a9b29 client_state: Make has_column_family_access use data_dictionary::database
Straightforward replacement. Internals of the has_column_family_access()
temporarily get .real_database(), but it will be changed soon.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2022-01-14 12:55:15 +03:00
Pavel Emelyanov
d98dd0ff80 cql3: Generalize bounce-to-shard result creation
The main intention is actually to free the qp.proxy() from the
need to provide the get_stats() method.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 11:28:44 +03:00
Pavel Emelyanov
d32de22ee8 cql3: Get data dictionary directly from query_processor
After previous patches there's a whole bunch of places that do

  qp.proxy().data_dictionary()

while the data_dictionary is present on the query processor itself
and there's a public method to get one. So use it everywhere.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 11:28:44 +03:00
Pavel Emelyanov
b29d3f1758 cas_request: Make read_command() accept query_processor
Just relpace the argument and patch the callers

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 10:54:28 +03:00
Pavel Emelyanov
7a15f1c402 batch_|modification_statement: Make get_mutations accept query_processor
This completes the batch_ and modification_statement rework.
Also touch the private batch_statement::read_command while at it.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 10:54:28 +03:00
Pavel Emelyanov
b1b230548b modification_statement: Replace most of proxy-s with query_processor
There are some internal methods that use proxy argument. Replace
most of them with query_processor, next patch will fix the rest --
those that interact with batch statement.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 10:54:28 +03:00
Pavel Emelyanov
bce2ed9c6c cql3: Make execution stages carry query_processor over
The batch_ , modification_ and select_ statements get proxy from
query processor just to push it through execution stage. Simplify
that by pushing the query processor itself.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 10:53:44 +03:00
Pavel Emelyanov
b990ca5550 cql3: Make .validate() and .check_access() accept query_processor
This is mostly a sed script that replaces methods' first argument
plus fixes of compiler-generated errors.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-12-23 10:53:44 +03:00
Avi Kivity
d768e9fac5 cql3, related: switch to data_dictionary
Stop using database (and including database.hh) for schema related
purposes and use data_dictionary instead.

data_dictionary::database::real_database() is called from several
places, for these reasons:

 - calling yet-to-be-converted code
 - callers with a legitimate need to access data (e.g. system_keyspace)
   but with the ::database accessor removed from query_processor.
   We'll need to find another way to supply system_keyspace with
   data access.
 - to gain access to the wasm engine for testing whether used
   defined functions compile. We'll have to find another way to
   do this as well.

The change is a straightforward replacement. One case in
modification_statement had to change a capture, but everything else
was just a search-and-replace.

Some files that lost "database.hh" gained "mutation.hh", which they
previously had access to through "database.hh".
2021-12-15 13:54:23 +02:00
Avi Kivity
595cc328b1 Merge 'cql3: Remove term, replace with expression' from Jan Ciołek
This PR finally removes the `term` class and replaces it with `expression`.

* There was some trouble with `lwt_cache_id` in `expr::function_call`.
  The current code works the following way:
  * for each `function_call` inside a `term` that describes a pk restriction, `prepare_context::add_pk_function_call` is called.
  * `add_pk_function_call` takes a `::shared_ptr<cql3::functions::function_call>`, sets its `cache_id` and pushes this shared pointer onto a vector of all collected function calls
  * Later when some condiition is met we want to clear cache ids of all those collected function calls. To do this we iterate through shared pointers collected in `prepare_context` and clear cache id for each of them.

  This doesn't work with `expr::function_call` because it isn't kept inside a shared pointer.
  To solve this I put the `lwt_cache_id` inside a shared pointer and then `prepare_context` collects these shared pointers to cache ids.

  I also experimented with doing this without any shared pointers, maybe we could just walk through the expression and clear the cache ids ourselves. But the problem is that expressions are copied all the time, we could clear the cache in one place, but forget about a copy. Doing it using shared pointers more closely matches the original behaviour.
The experiment is on the [term2-pr3-backup-altcache](https://github.com/cvybhu/scylla/tree/term2-pr3-backup-altcache) branch
* `shared_ptr<term>` being `nullptr` could mean:
  * It represents a cql value `null`
  * That there is no value, like `std::nullopt` (for example in `attributes.hh`)
  * That it's a mistake, it shouldn't be possible

  A good way to distinguish between optional and mistake is to look for `my_term->bind_and_get()`, we then know that it's not an optional value.

* On the other hand `raw_value` cased to bool means:
   * `false` - null or unset
   * `true` - some value, maybe empty

I ran a simple benchmark on my laptop to see how performance is affected:
```
build/release/test/perf/perf_simple_query --smp 1 -m 1G --operations-per-shard 1000000 --task-quota-ms 10
```
* On master (a21b1fbb2f) I get:
  ```
  176506.60 tps ( 77.0 allocs/op,  12.0 tasks/op,   45831 insns/op)

  median 176506.60 tps ( 77.0 allocs/op,  12.0 tasks/op,   45831 insns/op)
  median absolute deviation: 0.00
  maximum: 176506.60
  minimum: 176506.60
  ```
* On this branch I get:
  ```
  172225.30 tps ( 75.1 allocs/op,  12.1 tasks/op,   46106 insns/op)

  median 172225.30 tps ( 75.1 allocs/op,  12.1 tasks/op,   46106 insns/op)
  median absolute deviation: 0.00
  maximum: 172225.30
  minimum: 172225.30
  ```

Closes #9481

* github.com:scylladb/scylla:
  cql3: Remove remaining mentions of term
  cql3: Remove term
  cql3: Rename prepare_term to prepare_expression
  cql3: Make prepare_term return an expression instead of term
  cql3: expr: Add size check to evaluate_set
  cql3: expr: Add expr::contains_bind_marker
  cql3: expr: Rename find_atom to find_binop
  cql3: expr: Add find_in_expression
  cql3: Remove term in operations
  cql3: Remove term in relations
  cql3: Remove term in multi_column_restrictions
  cql3: Remove term in term_slice, rename to bounds_slice
  cql3: expr: Remove term in expression
  cql3: expr: Add evaluate_IN_list(expression, options)
  cql3: Remove term in column_condition
  cql3: Remove term in select_statement
  cql3: Remove term in update_statement
  cql3: Use internal cql format in insert_prepared_json_statement cache
  types: Add map_type_impl::serialize(range of <bytes, bytes>)
  cql3: Remove term in cql3/attributes
  cql3: expr: Add constant::view() method
  cql3: expr: Implement fill_prepare_context(expression)
  cql3: expr: add expr::visit that takes a mutable expression
  cql3: expr: Add receiver to expr::bind_variable
2021-11-30 16:39:39 +02:00
Jan Ciolek
c2eb3a58b8 cql3: expr: Implement fill_prepare_context(expression)
Adds a new function - expr::fill_prepare_context.
This function has the same functionality as term::fill_prepare_context, which will be removed soon.

fill_prepare_context used to take its argument with a const qualifier, but it turns out that the argume>
It sets the cache ids of function calls corresponding to partition key restrictions.
New function doesn't have const to make this clear and avoid surprises.

Added expr::visit that takes an argument without const qualifier.

There were some problems with cache_ids in function_call.
prepare_context used to collect ::shared_ptr<functions::function_call>
of some function call, and then this allowed it to clear
cache ids of all involved functions on demand.

To replicate this prepare_context now collects
shared pointers to expr::function_call cache ids.

It currently collects both, but functions::function_call will be removed soon.

Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2021-10-28 15:14:52 +02:00
Piotr Sarna
f4cb8191fa cql3: include system distributed tables in system stats
Some time ago we started gathering stats for system tables in a separate
class in order to be able to distinguish which queries come from the
user - e.g. if the unpaged queries are internal or not.
Originally, only local system tables were moved into this class,
i.e. system and system_schema. It would make sense, however, to also
include other internal keyspaces in this separate class - which includes
system_distributed, system_traces, etc.

Fixes #9380

Closes #9490
2021-10-28 08:58:25 +03:00
Piotr Sarna
7c35d47690 cql3: make column names readable for invalid delete statements
This commit makes the column names from an invalid delete statement human readable.
Before that, they were printed in their hex representation, which is not convenient
for debugging.

Before:
  InvalidRequest:
    Error from server: code=2200 [Invalid query]
    message="Invalid where clause contains non PRIMARY KEY columns: 76616c"
After:
  InvalidRequest:
    Error from server: code=2200 [Invalid query]
    message="Invalid where clause contains non PRIMARY KEY columns: val"
Message-Id: <52923335e8837295fd5ba2dfd0921196e21f7f16.1634626777.git.sarna@scylladb.com>
2021-10-19 10:13:43 +03:00
Dejan Mircevski
6afdc6004c cql3/modification_statement: Replace empty-range check with null check
The empty-range check causes more bugs than it fixes.  Replace it with
an explicit check for =NULL (see #7852).

Fixes #9311.
Fixes #9290.

Tests: unit (dev), cql-pytest on Cassandra 4.0

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>

Closes #9314
2021-09-09 10:56:13 +03:00
Dejan Mircevski
1fdaeca7d0 cql3: Reject updates with NULL key values
We were silently ignoring INSERTs with NULL values for primary-key
columns, which Cassandra rejects.  Fix it by rejecting any
modification_statement that would operate on empty partition or
clustering range.

This is the most direct fix, because range and slice are calculated in
one place for all modification statements.  It covers not only NULL
cases, but also impossible restrictions like c>0 AND c<0.
Unfortunately, Cassandra doesn't treat all modification statements
consistently, so this fix cannot fully match its behavior.  We err on
the side of tolerance, accepting some DELETE statements that Cassandra
rejects.  We add a TODO for rejecting such DELETEs later.

Fixes #7852.

Tests: unit (dev), cql-pytest against Cassandra 4.0

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>

Closes #9286
2021-09-05 10:23:28 +03:00
Pavel Solodovnikov
3b6adf3a62 cql3: cache function calls evaluation for non-deterministic functions
And reuse these values when handling `bounce_to_shard` messages.

Otherwise such a function (e.g. `uuid()`) can yield a different
value when a statement re-executed on the other shard.

It can lead to an infinite number of `bounce_to_shard` messages
sent in case the function value is used to calculate partition
key ranges for the query. Which, in turn, will cause crashes
since we don't support bouncing more than one time and the second
hop will result in a crash.

Caching works only for LWT statements and only for the function
calls that affect partition key range computation for the query.

`variable_specifications` class is renamed to `prepare_context`
and generalized to record information about each `function_call`
AST node and modify them, as needed:
* Check whether a given function call is a part of partition key
  statement restriction.
* Assign ids for caching if above is true and the call is a part
  of an LWT statement.

There is no need to include any kind of statement identifier
in the cache key since `query_options` (which holds the cache)
is limited to a single statement, anyway.

Note that `function_call::raw` AST nodes are not created
for selection clauses of a SELECT statement hence they
can only accept only one of the following things as parameters:
* Other function calls.
* Literal values.
* Parameter markers.

In other words, only parameters that can be immediately reduced
to a byte buffer are allowed and we don't need to handle
database inputs to non-pure functions separately since they
are not possible in this context. Anyhow, we don't even have
a single non-pure function that accepts arguments, so precautions
are not needed at the moment.

Tests: unit(dev, debug)

Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
2021-07-30 01:22:39 +03:00
Pavel Solodovnikov
49ddd269ea cql3: rename variable_specifications to prepare_context
The class is repurposed to be more generic and also be able
to hold additional metadata related to function calls within
a CQL statement. Rename all methods appropriately.

Visitor functions in AST nodes (`collect_marker_specification`)
are also renamed to a more generic `fill_prepare_context`.

The name `prepare_context` designates that this metadata
structure is a byproduct of `stmt::raw::prepare()` call and
is needed only for "prepare" step of query execution.

Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
2021-07-24 14:33:33 +03:00
Avi Kivity
a55b434a2b treewide: extent copyright statements to present day 2021-06-06 19:18:49 +03:00
Pavel Solodovnikov
2187a59089 treewide: move service::cas_request out from storage_proxy.hh
And remove all remaining inclusions of `storage_proxy.hh` in the
headers.

Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
2021-06-06 19:18:49 +03:00
Dejan Mircevski
962373a0a7 cql3: Replace some bounds_ranges calls
We will remove bounds_ranges when we kill the restrictions class
hierarchy.  Of the several call sites, two can be easily modified to
avoid it.  Others are more complicated and will be modified in a
subsequent commit.

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2021-04-23 15:01:39 -04:00
Pavel Emelyanov
26c115f379 cql3: Change execute()'s 1st arg to query_processor
Currently the statement's execute() method accepts storage
proxy as the first argument. This is enough for all of them
but schema altering ones, because the latter need to call
migration manager's announce.

To provide the migration manager to those who need it it's
needed to have some higher-level service that the proxy. The
query processor seems to be good candidate for it.

Said that -- all the .execute()s now accept the querty
processor instead of the proxy and get the proxy itself from
the query processor.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2021-03-15 19:00:33 +03:00
Piotr Sarna
639d90d2d6 cql3: use timeout config from client state instead of query options
... in modification statement, in order to be able to remove the timeout
from query options later.
2021-02-25 17:20:27 +01:00
Gleb Natapov
805da054e7 cql3: store cf_name as optional in cf_statement instead of shared_ptr
It been a shard_ptr is a remnant of translation from Java.
Message-Id: <20210216123931.80280-2-gleb@scylladb.com>
2021-02-16 15:58:37 +02:00
Piotr Sarna
f293c59a46 system_keyspace: migrate helper functions to string_view
Functions for checking if the keyspace is system/internal were based
on sstring references, which is impractical compared to string views
and may lead to unnecessary creation of sstring instances.
2021-01-04 09:47:01 +01:00
Piotr Sarna
3c49b6bd88 cql3: add per-query timeout to modification statement
If TIMEOUT attribute is set, it will be used as the effective
timeout for a particular query.
2020-12-14 07:50:40 +01:00
Pavel Emelyanov
b0c4a9087d client_state: Add database& arg to has_column_family_access
It is called from cql3/statements' check_access methods and from thrift
handlers. The former have proxy argument from which they can get the
database. The latter already have the database itself on board.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
2020-12-11 18:49:16 +03:00
Piotr Wojtczak
2150c0f7a2 cql: Check for timestamp correctness in USING TIMESTAMP statements
In certain CQL statements it's possible to provide a custom timestamp via the USING TIMESTAMP clause. Those values are accepted in microseconds, however, there's no limit on the timestamp (apart from type size constraint) and providing a timestamp in a different unit like nanoseconds can lead to creating an entry with a timestamp way ahead in the future, thus compromising the table.

To avoid this, this change introduces a sanity check for modification and batch statements that raises an error when a timestamp of more than 3 days into the future is provided.

Fixes #5619

Closes #7475
2020-11-01 11:01:24 +02:00
Dejan Mircevski
df3ea2443b cql3: Drop all uses_function methods
No one seems to call them except for other uses_function methods.

Tests: unit (dev)

Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
2020-09-04 17:27:30 +02:00
Pavel Solodovnikov
feaf2b6320 cas_request: move modification_statement::build_cas_result_set to cas_request
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>
2020-09-04 12:25:06 +03:00
Botond Dénes
92a7b16cba query: read_command: add max_result_size
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.
2020-07-28 18:00:29 +03:00
Avi Kivity
b0698dfb38 Merge 'Rewrite CQL3 restriction representation' from dekimir
"
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
2020-07-08 10:22:17 +03:00
Dejan Mircevski
37ebe521e3 cql3/restrictions: Use free functions instead of methods
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>
2020-07-07 23:08:09 +02:00
Pavel Solodovnikov
6c6f3dbe42 lwt: introduce "LWT" flag in prepared statement metadata
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>
2020-06-29 12:30:37 +03:00