Files
scylladb/cql3/selection/selection.cc
Piotr Sarna b0ab4c28cf schema: add column_definition::is_hidden_from_cql
Right now the only columns hidden from CQL are view virtual columns,
but in case of expanding this set, a helper function is provided.
2019-02-27 15:07:54 +01:00

489 lines
19 KiB
C++

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Copyright (C) 2015 ScyllaDB
*
* Modified by ScyllaDB
*/
/*
* This file is part of Scylla.
*
* Scylla is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Scylla is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
*/
#include <boost/range/adaptor/transformed.hpp>
#include <boost/range/adaptor/filtered.hpp>
#include "cql3/selection/selection.hh"
#include "cql3/selection/selector_factories.hh"
#include "cql3/result_set.hh"
#include "cql3/restrictions/multi_column_restriction.hh"
namespace cql3 {
namespace selection {
selection::selection(schema_ptr schema,
std::vector<const column_definition*> columns,
std::vector<::shared_ptr<column_specification>> metadata_,
bool collect_timestamps,
bool collect_TTLs,
trivial is_trivial)
: _schema(std::move(schema))
, _columns(std::move(columns))
, _metadata(::make_shared<metadata>(std::move(metadata_)))
, _collect_timestamps(collect_timestamps)
, _collect_TTLs(collect_TTLs)
, _contains_static_columns(std::any_of(_columns.begin(), _columns.end(), std::mem_fn(&column_definition::is_static)))
, _is_trivial(is_trivial)
{ }
query::partition_slice::option_set selection::get_query_options() {
query::partition_slice::option_set opts;
opts.set_if<query::partition_slice::option::send_timestamp>(_collect_timestamps);
opts.set_if<query::partition_slice::option::send_expiry>(_collect_TTLs);
opts.set_if<query::partition_slice::option::send_partition_key>(
std::any_of(_columns.begin(), _columns.end(),
std::mem_fn(&column_definition::is_partition_key)));
opts.set_if<query::partition_slice::option::send_clustering_key>(
std::any_of(_columns.begin(), _columns.end(),
std::mem_fn(&column_definition::is_clustering_key)));
return opts;
}
// Special cased selection for when no function is used (this save some allocations).
class simple_selection : public selection {
private:
const bool _is_wildcard;
public:
static ::shared_ptr<simple_selection> make(schema_ptr schema, std::vector<const column_definition*> columns, bool is_wildcard) {
std::vector<::shared_ptr<column_specification>> metadata;
metadata.reserve(columns.size());
for (auto&& col : columns) {
metadata.emplace_back(col->column_specification);
}
return ::make_shared<simple_selection>(schema, std::move(columns), std::move(metadata), is_wildcard);
}
/*
* In theory, even a simple selection could have multiple time the same column, so we
* could filter those duplicate out of columns. But since we're very unlikely to
* get much duplicate in practice, it's more efficient not to bother.
*/
simple_selection(schema_ptr schema, std::vector<const column_definition*> columns,
std::vector<::shared_ptr<column_specification>> metadata, bool is_wildcard)
: selection(schema, std::move(columns), std::move(metadata), false, false, trivial::yes)
, _is_wildcard(is_wildcard)
{ }
virtual bool is_wildcard() const override { return _is_wildcard; }
virtual bool is_aggregate() const override { return false; }
protected:
class simple_selectors : public selectors {
private:
std::vector<bytes_opt> _current;
public:
virtual void reset() override {
_current.clear();
}
virtual std::vector<bytes_opt> get_output_row(cql_serialization_format sf) override {
return std::move(_current);
}
virtual void add_input_row(cql_serialization_format sf, result_set_builder& rs) override {
_current = std::move(*rs.current);
}
virtual bool is_aggregate() {
return false;
}
};
std::unique_ptr<selectors> new_selectors() const override {
return std::make_unique<simple_selectors>();
}
};
class selection_with_processing : public selection {
private:
::shared_ptr<selector_factories> _factories;
public:
selection_with_processing(schema_ptr schema, std::vector<const column_definition*> columns,
std::vector<::shared_ptr<column_specification>> metadata, ::shared_ptr<selector_factories> factories)
: selection(schema, std::move(columns), std::move(metadata),
factories->contains_write_time_selector_factory(),
factories->contains_ttl_selector_factory())
, _factories(std::move(factories))
{
if (_factories->does_aggregation() && !_factories->contains_only_aggregate_functions()) {
throw exceptions::invalid_request_exception("the select clause must either contains only aggregates or none");
}
}
virtual bool uses_function(const sstring& ks_name, const sstring& function_name) const override {
return _factories->uses_function(ks_name, function_name);
}
virtual uint32_t add_column_for_post_processing(const column_definition& c) override {
uint32_t index = selection::add_column_for_post_processing(c);
_factories->add_selector_for_post_processing(c, index);
return index;
}
virtual bool is_aggregate() const override {
return _factories->contains_only_aggregate_functions();
}
protected:
class selectors_with_processing : public selectors {
private:
::shared_ptr<selector_factories> _factories;
std::vector<::shared_ptr<selector>> _selectors;
public:
selectors_with_processing(::shared_ptr<selector_factories> factories)
: _factories(std::move(factories))
, _selectors(_factories->new_instances())
{ }
virtual void reset() override {
for (auto&& s : _selectors) {
s->reset();
}
}
virtual bool is_aggregate() override {
return _factories->contains_only_aggregate_functions();
}
virtual std::vector<bytes_opt> get_output_row(cql_serialization_format sf) override {
std::vector<bytes_opt> output_row;
output_row.reserve(_selectors.size());
for (auto&& s : _selectors) {
output_row.emplace_back(s->get_output(sf));
}
return output_row;
}
virtual void add_input_row(cql_serialization_format sf, result_set_builder& rs) {
for (auto&& s : _selectors) {
s->add_input(sf, rs);
}
}
};
std::unique_ptr<selectors> new_selectors() const override {
return std::make_unique<selectors_with_processing>(_factories);
}
};
::shared_ptr<selection> selection::wildcard(schema_ptr schema) {
auto columns = schema->all_columns_in_select_order();
// filter out hidden columns, which should not be seen by the
// user when doing "SELECT *". We also disallow selecting them
// individually (see column_identifier::new_selector_factory()).
auto cds = boost::copy_range<std::vector<const column_definition*>>(
columns |
boost::adaptors::filtered([](const column_definition& c) {
return !c.is_hidden_from_cql();
}) |
boost::adaptors::transformed([](const column_definition& c) {
return &c;
}));
return simple_selection::make(schema, std::move(cds), true);
}
::shared_ptr<selection> selection::for_columns(schema_ptr schema, std::vector<const column_definition*> columns) {
return simple_selection::make(schema, std::move(columns), false);
}
uint32_t selection::add_column_for_post_processing(const column_definition& c) {
_columns.push_back(&c);
_metadata->add_non_serialized_column(c.column_specification);
return _columns.size() - 1;
}
::shared_ptr<selection> selection::from_selectors(database& db, schema_ptr schema, const std::vector<::shared_ptr<raw_selector>>& raw_selectors) {
std::vector<const column_definition*> defs;
::shared_ptr<selector_factories> factories =
selector_factories::create_factories_and_collect_column_definitions(
raw_selector::to_selectables(raw_selectors, schema), db, schema, defs);
auto metadata = collect_metadata(schema, raw_selectors, *factories);
if (processes_selection(raw_selectors) || raw_selectors.size() != defs.size()) {
return ::make_shared<selection_with_processing>(schema, std::move(defs), std::move(metadata), std::move(factories));
} else {
return ::make_shared<simple_selection>(schema, std::move(defs), std::move(metadata), false);
}
}
std::vector<::shared_ptr<column_specification>>
selection::collect_metadata(schema_ptr schema, const std::vector<::shared_ptr<raw_selector>>& raw_selectors,
const selector_factories& factories) {
std::vector<::shared_ptr<column_specification>> r;
r.reserve(raw_selectors.size());
auto i = raw_selectors.begin();
for (auto&& factory : factories) {
::shared_ptr<column_specification> col_spec = factory->get_column_specification(schema);
::shared_ptr<column_identifier> alias = (*i++)->alias;
r.push_back(alias ? col_spec->with_alias(alias) : col_spec);
}
return r;
}
result_set_builder::result_set_builder(const selection& s, gc_clock::time_point now, cql_serialization_format sf)
: _result_set(std::make_unique<result_set>(::make_shared<metadata>(*(s.get_result_metadata()))))
, _selectors(s.new_selectors())
, _now(now)
, _cql_serialization_format(sf)
{
if (s._collect_timestamps) {
_timestamps.resize(s._columns.size(), 0);
}
if (s._collect_TTLs) {
_ttls.resize(s._columns.size(), 0);
}
}
void result_set_builder::add_empty() {
current->emplace_back();
if (!_timestamps.empty()) {
_timestamps[current->size() - 1] = api::missing_timestamp;
}
if (!_ttls.empty()) {
_ttls[current->size() - 1] = -1;
}
}
void result_set_builder::add(bytes_opt value) {
current->emplace_back(std::move(value));
}
void result_set_builder::add(const column_definition& def, const query::result_atomic_cell_view& c) {
current->emplace_back(get_value(def.type, c));
if (!_timestamps.empty()) {
_timestamps[current->size() - 1] = c.timestamp();
}
if (!_ttls.empty()) {
gc_clock::duration ttl_left(-1);
expiry_opt e = c.expiry();
if (e) {
ttl_left = *e - _now;
}
_ttls[current->size() - 1] = ttl_left.count();
}
}
void result_set_builder::add_collection(const column_definition& def, bytes_view c) {
current->emplace_back(to_bytes(c));
// timestamps, ttls meaningless for collections
}
void result_set_builder::new_row() {
if (current) {
_selectors->add_input_row(_cql_serialization_format, *this);
if (!_selectors->is_aggregate()) {
_result_set->add_row(_selectors->get_output_row(_cql_serialization_format));
_selectors->reset();
}
current->clear();
} else {
// FIXME: we use optional<> here because we don't have an end_row() signal
// instead, !current means that new_row has never been called, so this
// call to new_row() does not end a previous row.
current.emplace();
}
}
std::unique_ptr<result_set> result_set_builder::build() {
if (current) {
_selectors->add_input_row(_cql_serialization_format, *this);
_result_set->add_row(_selectors->get_output_row(_cql_serialization_format));
_selectors->reset();
current = std::nullopt;
}
if (_result_set->empty() && _selectors->is_aggregate()) {
_result_set->add_row(_selectors->get_output_row(_cql_serialization_format));
}
return std::move(_result_set);
}
bool result_set_builder::restrictions_filter::do_filter(const selection& selection,
const std::vector<bytes>& partition_key,
const std::vector<bytes>& clustering_key,
const query::result_row_view& static_row,
const query::result_row_view& row) const {
static logging::logger rlogger("restrictions_filter");
if (_current_partition_key_does_not_match || _current_static_row_does_not_match || _remaining == 0 || _per_partition_remaining == 0) {
return false;
}
auto clustering_columns_restrictions = _restrictions->get_clustering_columns_restrictions();
if (clustering_columns_restrictions->is_multi_column()) {
auto multi_column_restriction = dynamic_pointer_cast<cql3::restrictions::multi_column_restriction>(clustering_columns_restrictions);
clustering_key_prefix ckey = clustering_key_prefix::from_exploded(clustering_key);
return multi_column_restriction->is_satisfied_by(*_schema, ckey, _options);
}
auto static_row_iterator = static_row.iterator();
auto row_iterator = row.iterator();
auto non_pk_restrictions_map = _restrictions->get_non_pk_restriction();
for (auto&& cdef : selection.get_columns()) {
switch (cdef->kind) {
case column_kind::static_column:
// fallthrough
case column_kind::regular_column: {
auto& cell_iterator = (cdef->kind == column_kind::static_column) ? static_row_iterator : row_iterator;
std::optional<query::result_bytes_view> result_view_opt;
if (cdef->type->is_multi_cell()) {
result_view_opt = cell_iterator.next_collection_cell();
} else {
auto cell = cell_iterator.next_atomic_cell();
if (cell) {
result_view_opt = cell->value();
}
}
auto restr_it = non_pk_restrictions_map.find(cdef);
if (restr_it == non_pk_restrictions_map.end()) {
continue;
}
restrictions::single_column_restriction& restriction = *restr_it->second;
bool regular_restriction_matches;
if (result_view_opt) {
regular_restriction_matches = result_view_opt->with_linearized([&restriction, this](bytes_view data) {
return restriction.is_satisfied_by(data, _options);
});
} else {
regular_restriction_matches = restriction.is_satisfied_by(bytes(), _options);
}
if (!regular_restriction_matches) {
_current_static_row_does_not_match = (cdef->kind == column_kind::static_column);
return false;
}
}
break;
case column_kind::partition_key: {
if (_skip_pk_restrictions) {
continue;
}
auto partition_key_restrictions_map = _restrictions->get_single_column_partition_key_restrictions();
auto restr_it = partition_key_restrictions_map.find(cdef);
if (restr_it == partition_key_restrictions_map.end()) {
continue;
}
restrictions::single_column_restriction& restriction = *restr_it->second;
const bytes& value_to_check = partition_key[cdef->id];
bool pk_restriction_matches = restriction.is_satisfied_by(value_to_check, _options);
if (!pk_restriction_matches) {
_current_partition_key_does_not_match = true;
return false;
}
}
break;
case column_kind::clustering_key: {
if (_skip_ck_restrictions) {
continue;
}
auto clustering_key_restrictions_map = _restrictions->get_single_column_clustering_key_restrictions();
auto restr_it = clustering_key_restrictions_map.find(cdef);
if (restr_it == clustering_key_restrictions_map.end()) {
continue;
}
restrictions::single_column_restriction& restriction = *restr_it->second;
const bytes& value_to_check = clustering_key[cdef->id];
bool pk_restriction_matches = restriction.is_satisfied_by(value_to_check, _options);
if (!pk_restriction_matches) {
return false;
}
}
break;
default:
break;
}
}
return true;
}
bool result_set_builder::restrictions_filter::operator()(const selection& selection,
const std::vector<bytes>& partition_key,
const std::vector<bytes>& clustering_key,
const query::result_row_view& static_row,
const query::result_row_view& row) const {
const bool accepted = do_filter(selection, partition_key, clustering_key, static_row, row);
if (!accepted) {
++_rows_dropped;
} else {
if (_remaining > 0) {
--_remaining;
}
if (_per_partition_remaining > 0) {
--_per_partition_remaining;
}
}
return accepted;
}
void result_set_builder::restrictions_filter::reset(const partition_key* key) {
_current_partition_key_does_not_match = false;
_current_static_row_does_not_match = false;
_rows_dropped = 0;
_per_partition_remaining = _per_partition_limit;
if (_is_first_partition_on_page && _per_partition_limit < std::numeric_limits<typeof(_per_partition_limit)>::max()) {
// If any rows related to this key were also present in the previous query,
// we need to take it into account as well.
if (key && _last_pkey && _last_pkey->equal(*_schema, *key)) {
_per_partition_remaining -= _rows_fetched_for_last_partition;
}
_is_first_partition_on_page = false;
}
}
api::timestamp_type result_set_builder::timestamp_of(size_t idx) {
return _timestamps[idx];
}
int32_t result_set_builder::ttl_of(size_t idx) {
return _ttls[idx];
}
bytes_opt result_set_builder::get_value(data_type t, query::result_atomic_cell_view c) {
return {c.value().linearize()};
}
}
}