Files
scylla/cql3/restrictions/statement_restrictions.cc
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

1754 lines
81 KiB
C++

/*
* Copyright (C) 2015-present 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 <algorithm>
#include <boost/algorithm/cxx11/all_of.hpp>
#include <boost/algorithm/cxx11/any_of.hpp>
#include <boost/range/adaptors.hpp>
#include <boost/range/algorithm.hpp>
#include <functional>
#include <ranges>
#include <stdexcept>
#include "query-result-reader.hh"
#include "statement_restrictions.hh"
#include "multi_column_restriction.hh"
#include "token_restriction.hh"
#include "data_dictionary/data_dictionary.hh"
#include "cartesian_product.hh"
#include "cql3/constants.hh"
#include "cql3/lists.hh"
#include "cql3/selection/selection.hh"
#include "cql3/single_column_relation.hh"
#include "cql3/statements/request_validations.hh"
#include "types/list.hh"
#include "types/map.hh"
#include "types/set.hh"
namespace cql3 {
namespace restrictions {
static logging::logger rlogger("restrictions");
using boost::adaptors::filtered;
using boost::adaptors::transformed;
using statements::request_validations::invalid_request;
template<typename T>
class statement_restrictions::initial_key_restrictions : public primary_key_restrictions<T> {
bool _allow_filtering;
public:
initial_key_restrictions(bool allow_filtering)
: _allow_filtering(allow_filtering) {
this->expression = expr::constant::make_bool(true);
}
::shared_ptr<primary_key_restrictions<T>> do_merge_to(schema_ptr schema, ::shared_ptr<restriction> restriction) const {
return ::make_shared<single_column_primary_key_restrictions<T>>(schema, _allow_filtering)->merge_to(schema, restriction);
}
::shared_ptr<primary_key_restrictions<T>> merge_to(schema_ptr schema, ::shared_ptr<restriction> restriction) override {
if (has_token(restriction->expression)) {
return static_pointer_cast<token_restriction>(restriction);
}
return ::make_shared<single_column_primary_key_restrictions<T>>(schema, _allow_filtering)->merge_to(restriction);
}
void merge_with(::shared_ptr<restriction> restriction) override {
throw exceptions::unsupported_operation_exception();
}
bytes_opt value_for(const column_definition& cdef, const query_options& options) const override {
return {};
}
std::vector<const column_definition*> get_column_defs() const override {
// throw? should not reach?
return {};
}
bool empty() const override {
return true;
}
uint32_t size() const override {
return 0;
}
virtual bool has_supporting_index(const secondary_index::secondary_index_manager& index_manager,
expr::allow_local_index allow_local) const override {
return false;
}
};
template<>
::shared_ptr<primary_key_restrictions<partition_key>>
statement_restrictions::initial_key_restrictions<partition_key>::merge_to(schema_ptr schema, ::shared_ptr<restriction> restriction) {
if (has_token(restriction->expression)) {
return static_pointer_cast<token_restriction>(restriction);
}
return do_merge_to(std::move(schema), std::move(restriction));
}
template<>
::shared_ptr<primary_key_restrictions<clustering_key_prefix>>
statement_restrictions::initial_key_restrictions<clustering_key_prefix>::merge_to(schema_ptr schema, ::shared_ptr<restriction> restriction) {
if (auto p = dynamic_pointer_cast<multi_column_restriction>(restriction)) {
return p;
}
return do_merge_to(std::move(schema), std::move(restriction));
}
::shared_ptr<partition_key_restrictions> statement_restrictions::get_initial_partition_key_restrictions(bool allow_filtering) {
static thread_local ::shared_ptr<partition_key_restrictions> initial_kr_true = ::make_shared<initial_key_restrictions<partition_key>>(true);
static thread_local ::shared_ptr<partition_key_restrictions> initial_kr_false = ::make_shared<initial_key_restrictions<partition_key>>(false);
return allow_filtering ? initial_kr_true : initial_kr_false;
}
::shared_ptr<clustering_key_restrictions> statement_restrictions::get_initial_clustering_key_restrictions(bool allow_filtering) {
static thread_local ::shared_ptr<clustering_key_restrictions> initial_kr_true = ::make_shared<initial_key_restrictions<clustering_key>>(true);
static thread_local ::shared_ptr<clustering_key_restrictions> initial_kr_false = ::make_shared<initial_key_restrictions<clustering_key>>(false);
return allow_filtering ? initial_kr_true : initial_kr_false;
}
statement_restrictions::statement_restrictions(schema_ptr schema, bool allow_filtering)
: _schema(schema)
, _partition_key_restrictions(get_initial_partition_key_restrictions(allow_filtering))
, _clustering_columns_restrictions(get_initial_clustering_key_restrictions(allow_filtering))
, _nonprimary_key_restrictions(::make_shared<single_column_restrictions>(schema))
, _partition_range_is_simple(true)
{ }
#if 0
static const column_definition*
to_column_definition(const schema_ptr& schema, const ::shared_ptr<column_identifier::raw>& entity) {
return get_column_definition(schema,
*entity->prepare_column_identifier(schema));
}
#endif
template <typename Visitor>
concept visitor_with_binary_operator_context = requires (Visitor v) {
{ v.current_binary_operator } -> std::convertible_to<const expr::binary_operator*>;
};
void with_current_binary_operator(
visitor_with_binary_operator_context auto& visitor,
std::invocable<const expr::binary_operator&> auto func) {
if (!visitor.current_binary_operator) {
throw std::logic_error("Evaluation expected within binary operator");
}
func(*visitor.current_binary_operator);
}
/// Every token, or if no tokens, an EQ/IN of every single PK column.
static std::vector<expr::expression> extract_partition_range(
const expr::expression& where_clause, schema_ptr schema) {
using namespace expr;
struct {
std::optional<expression> tokens;
std::unordered_map<const column_definition*, expression> single_column;
const binary_operator* current_binary_operator = nullptr;
void operator()(const conjunction& c) {
std::ranges::for_each(c.children, [this] (const expression& child) { expr::visit(*this, child); });
}
void operator()(const binary_operator& b) {
if (current_binary_operator) {
throw std::logic_error("Nested binary operators are not supported");
}
current_binary_operator = &b;
expr::visit(*this, b.lhs);
current_binary_operator = nullptr;
}
void operator()(const token&) {
with_current_binary_operator(*this, [&] (const binary_operator& b) {
if (tokens) {
tokens = make_conjunction(std::move(*tokens), b);
} else {
tokens = b;
}
});
}
void operator()(const column_value& cv) {
auto s = &cv;
with_current_binary_operator(*this, [&] (const binary_operator& b) {
if (s->col->is_partition_key() && (b.op == oper_t::EQ || b.op == oper_t::IN)) {
const auto found = single_column.find(s->col);
if (found == single_column.end()) {
single_column[s->col] = b;
} else {
found->second = make_conjunction(std::move(found->second), b);
}
}
});
}
void operator()(const tuple_constructor& s) {
// Partition key columns are not legal in tuples, so ignore tuples.
}
void operator()(const constant&) {}
void operator()(const unresolved_identifier&) {
on_internal_error(rlogger, "extract_partition_range(unresolved_identifier)");
}
void operator()(const column_mutation_attribute&) {
on_internal_error(rlogger, "extract_partition_range(column_mutation_attribute)");
}
void operator()(const function_call&) {
on_internal_error(rlogger, "extract_partition_range(function_call)");
}
void operator()(const cast&) {
on_internal_error(rlogger, "extract_partition_range(cast)");
}
void operator()(const field_selection&) {
on_internal_error(rlogger, "extract_partition_range(field_selection)");
}
void operator()(const null&) {
on_internal_error(rlogger, "extract_partition_range(null)");
}
void operator()(const bind_variable&) {
on_internal_error(rlogger, "extract_partition_range(bind_variable)");
}
void operator()(const untyped_constant&) {
on_internal_error(rlogger, "extract_partition_range(untyped_constant)");
}
void operator()(const collection_constructor&) {
on_internal_error(rlogger, "extract_partition_range(collection_constructor)");
}
void operator()(const usertype_constructor&) {
on_internal_error(rlogger, "extract_partition_range(usertype_constructor)");
}
} v;
expr::visit(v, where_clause);
if (v.tokens) {
return {std::move(*v.tokens)};
}
if (v.single_column.size() == schema->partition_key_size()) {
return boost::copy_range<std::vector<expression>>(v.single_column | boost::adaptors::map_values);
}
return {};
}
/// Extracts where_clause atoms with clustering-column LHS and copies them to a vector. These elements define the
/// boundaries of any clustering slice that can possibly meet where_clause. This vector can be calculated before
/// binding expression markers, since LHS and operator are always known.
static std::vector<expr::expression> extract_clustering_prefix_restrictions(
const expr::expression& where_clause, schema_ptr schema) {
using namespace expr;
/// Collects all clustering-column restrictions from an expression. Presumes the expression only uses
/// conjunction to combine subexpressions.
struct visitor {
std::vector<expression> multi; ///< All multi-column restrictions.
/// All single-clustering-column restrictions, grouped by column. Each value is either an atom or a
/// conjunction of atoms.
std::unordered_map<const column_definition*, expression> single;
const binary_operator* current_binary_operator = nullptr;
void operator()(const conjunction& c) {
std::ranges::for_each(c.children, [this] (const expression& child) { expr::visit(*this, child); });
}
void operator()(const binary_operator& b) {
if (current_binary_operator) {
throw std::logic_error("Nested binary operators are not supported");
}
current_binary_operator = &b;
expr::visit(*this, b.lhs);
current_binary_operator = nullptr;
}
void operator()(const tuple_constructor& tc) {
for (auto& e : tc.elements) {
if (!expr::is<column_value>(e)) {
on_internal_error(rlogger, fmt::format("extract_clustering_prefix_restrictions: tuple of non-column_value: {}", tc));
}
}
with_current_binary_operator(*this, [&] (const binary_operator& b) {
multi.push_back(b);
});
}
void operator()(const column_value& cv) {
auto s = &cv;
with_current_binary_operator(*this, [&] (const binary_operator& b) {
if (s->col->is_clustering_key()) {
const auto found = single.find(s->col);
if (found == single.end()) {
single[s->col] = b;
} else {
found->second = make_conjunction(std::move(found->second), b);
}
}
});
}
void operator()(const token&) {
// A token cannot be a clustering prefix restriction
}
void operator()(const constant&) {}
void operator()(const unresolved_identifier&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(unresolved_identifier)");
}
void operator()(const column_mutation_attribute&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(column_mutation_attribute)");
}
void operator()(const function_call&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(function_call)");
}
void operator()(const cast&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(cast)");
}
void operator()(const field_selection&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(field_selection)");
}
void operator()(const null&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(null)");
}
void operator()(const bind_variable&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(bind_variable)");
}
void operator()(const untyped_constant&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(untyped_constant)");
}
void operator()(const collection_constructor&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(collection_constructor)");
}
void operator()(const usertype_constructor&) {
on_internal_error(rlogger, "extract_clustering_prefix_restrictions(usertype_constructor)");
}
} v;
expr::visit(v, where_clause);
if (!v.multi.empty()) {
return move(v.multi);
}
std::vector<expression> prefix;
for (const auto& col : schema->clustering_key_columns()) {
const auto found = v.single.find(&col);
if (found == v.single.end()) { // Any further restrictions are skipping the CK order.
break;
}
if (find_needs_filtering(found->second)) { // This column's restriction doesn't define a clear bound.
// TODO: if this is a conjunction of filtering and non-filtering atoms, we could split them and add the
// latter to the prefix.
break;
}
prefix.push_back(found->second);
if (has_slice(found->second)) {
break;
}
}
return prefix;
}
statement_restrictions::statement_restrictions(data_dictionary::database db,
schema_ptr schema,
statements::statement_type type,
const std::vector<::shared_ptr<relation>>& where_clause,
prepare_context& ctx,
bool selects_only_static_columns,
bool for_view,
bool allow_filtering)
: statement_restrictions(schema, allow_filtering)
{
if (!where_clause.empty()) {
for (auto&& relation : where_clause) {
if (relation->get_operator() == expr::oper_t::IS_NOT) {
single_column_relation* r =
dynamic_cast<single_column_relation*>(relation.get());
// The "IS NOT NULL" restriction is only supported (and
// mandatory) for materialized view creation:
if (!r) {
throw exceptions::invalid_request_exception("IS NOT only supports single column");
}
// currently, the grammar only allows the NULL argument to be
// "IS NOT", so this assertion should not be able to fail
assert(expr::is<expr::null>(*r->get_value()));
auto col_id = r->get_entity()->prepare_column_identifier(*schema);
const auto *cd = get_column_definition(*schema, *col_id);
if (!cd) {
throw exceptions::invalid_request_exception(format("restriction '{}' unknown column {}", relation->to_string(), r->get_entity()->to_string()));
}
_not_null_columns.insert(cd);
if (!for_view) {
throw exceptions::invalid_request_exception(format("restriction '{}' is only supported in materialized view creation", relation->to_string()));
}
} else {
const auto restriction = relation->to_restriction(db, schema, ctx);
if (dynamic_pointer_cast<multi_column_restriction>(restriction)) {
_clustering_columns_restrictions = _clustering_columns_restrictions->merge_to(_schema, restriction);
} else if (has_token(restriction->expression)) {
_partition_key_restrictions = _partition_key_restrictions->merge_to(_schema, restriction);
} else {
auto single = ::static_pointer_cast<single_column_restriction>(restriction);
auto& def = single->get_column_def();
if (def.is_partition_key()) {
// View definition allows PK slices, because it's not a performance problem.
if (has_slice(restriction->expression) && !allow_filtering && !for_view) {
throw exceptions::invalid_request_exception(
"Only EQ and IN relation are supported on the partition key "
"(unless you use the token() function or allow filtering)");
}
_partition_key_restrictions = _partition_key_restrictions->merge_to(_schema, restriction);
_partition_range_is_simple &= !find(restriction->expression, expr::oper_t::IN);
} else if (def.is_clustering_key()) {
_clustering_columns_restrictions = _clustering_columns_restrictions->merge_to(_schema, restriction);
} else {
_nonprimary_key_restrictions->add_restriction(single);
}
}
_where = _where.has_value() ? make_conjunction(std::move(*_where), restriction->expression) : restriction->expression;
}
}
}
if (_where.has_value()) {
_clustering_prefix_restrictions = extract_clustering_prefix_restrictions(*_where, _schema);
_partition_range_restrictions = extract_partition_range(*_where, _schema);
}
auto cf = db.find_column_family(schema);
auto& sim = cf.get_index_manager();
const expr::allow_local_index allow_local(
!_partition_key_restrictions->has_unrestricted_components(*_schema)
&& _partition_key_restrictions->is_all_eq());
_has_multi_column = find_binop(_clustering_columns_restrictions->expression, expr::is_multi_column);
_has_queriable_ck_index = _clustering_columns_restrictions->has_supporting_index(sim, allow_local)
&& !type.is_delete();
_has_queriable_pk_index = _partition_key_restrictions->has_supporting_index(sim, allow_local)
&& !type.is_delete();
_has_queriable_regular_index = _nonprimary_key_restrictions->has_supporting_index(sim, allow_local)
&& !type.is_delete();
// At this point, the select statement if fully constructed, but we still have a few things to validate
process_partition_key_restrictions(for_view, allow_filtering);
// Some but not all of the partition key columns have been specified;
// hence we need turn these restrictions into index expressions.
if (_uses_secondary_indexing || _partition_key_restrictions->needs_filtering(*_schema)) {
_index_restrictions.push_back(_partition_key_restrictions);
}
// If the only updated/deleted columns are static, then we don't need clustering columns.
// And in fact, unless it is an INSERT, we reject if clustering columns are provided as that
// suggest something unintended. For instance, given:
// CREATE TABLE t (k int, v int, s int static, PRIMARY KEY (k, v))
// it can make sense to do:
// INSERT INTO t(k, v, s) VALUES (0, 1, 2)
// but both
// UPDATE t SET s = 3 WHERE k = 0 AND v = 1
// DELETE s FROM t WHERE k = 0 AND v = 1
// sounds like you don't really understand what your are doing.
if (selects_only_static_columns && has_clustering_columns_restriction()) {
if (type.is_update() || type.is_delete()) {
throw exceptions::invalid_request_exception(format("Invalid restrictions on clustering columns since the {} statement modifies only static columns", type));
}
if (type.is_select()) {
throw exceptions::invalid_request_exception(
"Cannot restrict clustering columns when selecting only static columns");
}
}
process_clustering_columns_restrictions(for_view, allow_filtering);
// Covers indexes on the first clustering column (among others).
if (_is_key_range && _has_queriable_ck_index && !_has_multi_column) {
_uses_secondary_indexing = true;
}
if (_uses_secondary_indexing || _clustering_columns_restrictions->needs_filtering(*_schema)) {
_index_restrictions.push_back(_clustering_columns_restrictions);
} else if (find_binop(_clustering_columns_restrictions->expression, expr::is_on_collection)) {
fail(unimplemented::cause::INDEXES);
#if 0
_index_restrictions.push_back(new Forwardingprimary_key_restrictions() {
@Override
protected primary_key_restrictions getDelegate()
{
return _clustering_columns_restrictions;
}
@Override
public void add_index_expression_to(List<::shared_ptr<index_expression>> expressions, const query_options& options) throws InvalidRequestException
{
List<::shared_ptr<index_expression>> list = new ArrayList<>();
super.add_index_expression_to(list, options);
for (::shared_ptr<index_expression> expression : list)
{
if (expression.is_contains() || expression.is_containsKey())
expressions.add(expression);
}
}
});
uses_secondary_indexing = true;
#endif
}
if (!_nonprimary_key_restrictions->empty()) {
if (_has_queriable_regular_index) {
_uses_secondary_indexing = true;
} else if (!allow_filtering) {
throw exceptions::invalid_request_exception("Cannot execute this query as it might involve data filtering and "
"thus may have unpredictable performance. If you want to execute "
"this query despite the performance unpredictability, use ALLOW FILTERING");
}
_index_restrictions.push_back(_nonprimary_key_restrictions);
}
if (_uses_secondary_indexing && !(for_view || allow_filtering)) {
validate_secondary_index_selections(selects_only_static_columns);
}
}
const std::vector<::shared_ptr<restrictions>>& statement_restrictions::index_restrictions() const {
return _index_restrictions;
}
// Current score table:
// local and restrictions include full partition key: 2
// global: 1
// local and restrictions does not include full partition key: 0 (do not pick)
int statement_restrictions::score(const secondary_index::index& index) const {
if (index.metadata().local()) {
const bool allow_local = !_partition_key_restrictions->has_unrestricted_components(*_schema) && _partition_key_restrictions->is_all_eq();
return allow_local ? 2 : 0;
}
return 1;
}
namespace {
using namespace cql3::restrictions;
/// If rs contains a restrictions_map of individual columns to their restrictions, returns it. Otherwise, returns null.
const single_column_restrictions::restrictions_map* get_individual_restrictions_map(const restrictions* rs) {
if (auto regular = dynamic_cast<const single_column_restrictions*>(rs)) {
return &regular->restrictions();
} else if (auto partition = dynamic_cast<const single_column_partition_key_restrictions*>(rs)) {
return &partition->restrictions();
} else if (auto clustering = dynamic_cast<const single_column_clustering_key_restrictions*>(rs)) {
return &clustering->restrictions();
}
return nullptr;
}
} // anonymous namespace
std::pair<std::optional<secondary_index::index>, ::shared_ptr<cql3::restrictions::restrictions>> statement_restrictions::find_idx(const secondary_index::secondary_index_manager& sim) const {
std::optional<secondary_index::index> chosen_index;
int chosen_index_score = 0;
::shared_ptr<cql3::restrictions::restrictions> chosen_index_restrictions;
for (const auto& index : sim.list_indexes()) {
auto cdef = _schema->get_column_definition(to_bytes(index.target_column()));
for (::shared_ptr<cql3::restrictions::restrictions> restriction : index_restrictions()) {
if (auto rmap = get_individual_restrictions_map(restriction.get())) {
const auto found = rmap->find(cdef);
if (found != rmap->end() && is_supported_by(found->second->expression, index)
&& score(index) > chosen_index_score) {
chosen_index = index;
chosen_index_score = score(index);
chosen_index_restrictions = restriction;
}
}
}
}
return {chosen_index, chosen_index_restrictions};
}
bool statement_restrictions::has_eq_restriction_on_column(const column_definition& column) const {
if (!_where.has_value()) {
return false;
}
return expr::has_eq_restriction_on_column(column, *_where);
}
std::vector<const column_definition*> statement_restrictions::get_column_defs_for_filtering(data_dictionary::database db) const {
std::vector<const column_definition*> column_defs_for_filtering;
if (need_filtering()) {
auto& sim = db.find_column_family(_schema).get_index_manager();
auto opt_idx = std::get<0>(find_idx(sim));
auto column_uses_indexing = [&opt_idx] (const column_definition* cdef, ::shared_ptr<single_column_restriction> restr) {
return opt_idx && restr && is_supported_by(restr->expression, *opt_idx);
};
auto single_pk_restrs = dynamic_pointer_cast<single_column_partition_key_restrictions>(_partition_key_restrictions);
if (_partition_key_restrictions->needs_filtering(*_schema)) {
for (auto&& cdef : _partition_key_restrictions->get_column_defs()) {
::shared_ptr<single_column_restriction> restr;
if (single_pk_restrs) {
auto it = single_pk_restrs->restrictions().find(cdef);
if (it != single_pk_restrs->restrictions().end()) {
restr = dynamic_pointer_cast<single_column_restriction>(it->second);
}
}
if (!column_uses_indexing(cdef, restr)) {
column_defs_for_filtering.emplace_back(cdef);
}
}
}
auto single_ck_restrs = dynamic_pointer_cast<single_column_clustering_key_restrictions>(_clustering_columns_restrictions);
const bool pk_has_unrestricted_components = _partition_key_restrictions->has_unrestricted_components(*_schema);
if (pk_has_unrestricted_components || _clustering_columns_restrictions->needs_filtering(*_schema)) {
column_id first_filtering_id = pk_has_unrestricted_components ? 0 : _schema->clustering_key_columns().begin()->id +
_clustering_columns_restrictions->num_prefix_columns_that_need_not_be_filtered();
for (auto&& cdef : _clustering_columns_restrictions->get_column_defs()) {
::shared_ptr<single_column_restriction> restr;
if (single_ck_restrs) {
auto it = single_ck_restrs->restrictions().find(cdef);
if (it != single_ck_restrs->restrictions().end()) {
restr = dynamic_pointer_cast<single_column_restriction>(it->second);
}
}
if (cdef->id >= first_filtering_id && !column_uses_indexing(cdef, restr)) {
column_defs_for_filtering.emplace_back(cdef);
}
}
}
for (auto&& cdef : _nonprimary_key_restrictions->get_column_defs()) {
auto restr = dynamic_pointer_cast<single_column_restriction>(_nonprimary_key_restrictions->get_restriction(*cdef));
if (!column_uses_indexing(cdef, restr)) {
column_defs_for_filtering.emplace_back(cdef);
}
}
}
return column_defs_for_filtering;
}
void statement_restrictions::process_partition_key_restrictions(bool for_view, bool allow_filtering) {
// If there is a queriable index, no special condition are required on the other restrictions.
// But we still need to know 2 things:
// - If we don't have a queriable index, is the query ok
// - Is it queriable without 2ndary index, which is always more efficient
// If a component of the partition key is restricted by a relation, all preceding
// components must have a EQ. Only the last partition key component can be in IN relation.
if (has_token(_partition_key_restrictions->expression)) {
_is_key_range = true;
} else if (_partition_key_restrictions->empty()) {
_is_key_range = true;
_uses_secondary_indexing = _has_queriable_pk_index;
}
if (_partition_key_restrictions->needs_filtering(*_schema)) {
if (!allow_filtering && !for_view && !_has_queriable_pk_index) {
throw exceptions::invalid_request_exception("Cannot execute this query as it might involve data filtering and "
"thus may have unpredictable performance. If you want to execute "
"this query despite the performance unpredictability, use ALLOW FILTERING");
}
_is_key_range = true;
_uses_secondary_indexing = _has_queriable_pk_index;
}
}
bool statement_restrictions::has_partition_key_unrestricted_components() const {
return _partition_key_restrictions->has_unrestricted_components(*_schema);
}
bool statement_restrictions::has_unrestricted_clustering_columns() const {
return _clustering_columns_restrictions->has_unrestricted_components(*_schema);
}
void statement_restrictions::process_clustering_columns_restrictions(bool for_view, bool allow_filtering) {
if (!has_clustering_columns_restriction()) {
return;
}
if (find_binop(_clustering_columns_restrictions->expression, expr::is_on_collection)
&& !_has_queriable_ck_index && !allow_filtering) {
throw exceptions::invalid_request_exception(
"Cannot restrict clustering columns by a CONTAINS relation without a secondary index or filtering");
}
if (has_clustering_columns_restriction() && _clustering_columns_restrictions->needs_filtering(*_schema)) {
if (_has_queriable_ck_index) {
_uses_secondary_indexing = true;
} else if (!allow_filtering && !for_view) {
auto clustering_columns_iter = _schema->clustering_key_columns().begin();
for (auto&& restricted_column : _clustering_columns_restrictions->get_column_defs()) {
const column_definition* clustering_column = &(*clustering_columns_iter);
++clustering_columns_iter;
if (clustering_column != restricted_column) {
throw exceptions::invalid_request_exception(format("PRIMARY KEY column \"{}\" cannot be restricted as preceding column \"{}\" is not restricted",
restricted_column->name_as_text(), clustering_column->name_as_text()));
}
}
}
}
}
namespace {
using namespace expr;
/// Computes partition-key ranges from token atoms in ex.
dht::partition_range_vector partition_ranges_from_token(const expr::expression& ex, const query_options& options) {
auto values = possible_lhs_values(nullptr, ex, options);
if (values == expr::value_set(expr::value_list{})) {
return {};
}
const auto bounds = expr::to_range(values);
const auto start_token = bounds.start() ? bounds.start()->value().with_linearized([] (bytes_view bv) { return dht::token::from_bytes(bv); })
: dht::minimum_token();
auto end_token = bounds.end() ? bounds.end()->value().with_linearized([] (bytes_view bv) { return dht::token::from_bytes(bv); })
: dht::maximum_token();
const bool include_start = bounds.start() && bounds.start()->is_inclusive();
const auto include_end = bounds.end() && bounds.end()->is_inclusive();
auto start = dht::partition_range::bound(include_start
? dht::ring_position::starting_at(start_token)
: dht::ring_position::ending_at(start_token));
auto end = dht::partition_range::bound(include_end
? dht::ring_position::ending_at(end_token)
: dht::ring_position::starting_at(end_token));
return {{std::move(start), std::move(end)}};
}
/// Turns a partition-key value into a partition_range. \p pk must have elements for all partition columns.
dht::partition_range range_from_bytes(const schema& schema, const std::vector<managed_bytes>& pk) {
const auto k = partition_key::from_exploded(pk);
const auto tok = dht::get_token(schema, k);
const query::ring_position pos(std::move(tok), std::move(k));
return dht::partition_range::make_singular(std::move(pos));
}
void error_if_exceeds(size_t size, size_t limit) {
if (size > limit) {
throw std::runtime_error(
fmt::format("clustering-key cartesian product size {} is greater than maximum {}", size, limit));
}
}
/// Computes partition-key ranges from expressions, which contains EQ/IN for every partition column.
dht::partition_range_vector partition_ranges_from_singles(
const std::vector<expr::expression>& expressions, const query_options& options, const schema& schema) {
const size_t size_limit =
options.get_cql_config().restrictions.partition_key_restrictions_max_cartesian_product_size;
// Each element is a vector of that column's possible values:
std::vector<std::vector<managed_bytes>> column_values(schema.partition_key_size());
size_t product_size = 1;
for (const auto& e : expressions) {
if (const auto arbitrary_binop = find_binop(e, [] (const binary_operator&) { return true; })) {
if (auto cv = expr::as_if<expr::column_value>(&arbitrary_binop->lhs)) {
const value_set vals = possible_lhs_values(cv->col, e, options);
if (auto lst = std::get_if<value_list>(&vals)) {
if (lst->empty()) {
return {};
}
product_size *= lst->size();
error_if_exceeds(product_size, size_limit);
column_values[schema.position(*cv->col)] = move(*lst);
} else {
throw exceptions::invalid_request_exception(
"Only EQ and IN relation are supported on the partition key "
"(unless you use the token() function or allow filtering)");
}
}
}
}
cartesian_product cp(column_values);
dht::partition_range_vector ranges(product_size);
std::transform(cp.begin(), cp.end(), ranges.begin(), std::bind_front(range_from_bytes, std::ref(schema)));
return ranges;
}
/// Computes partition-key ranges from EQ restrictions on each partition column. Returns a single singleton range if
/// the EQ restrictions are not mutually conflicting. Otherwise, returns an empty vector.
dht::partition_range_vector partition_ranges_from_EQs(
const std::vector<expr::expression>& eq_expressions, const query_options& options, const schema& schema) {
std::vector<managed_bytes> pk_value(schema.partition_key_size());
for (const auto& e : eq_expressions) {
const auto col = expr::as<column_value>(find(e, oper_t::EQ)->lhs).col;
const auto vals = std::get<value_list>(possible_lhs_values(col, e, options));
if (vals.empty()) { // Case of C=1 AND C=2.
return {};
}
pk_value[schema.position(*col)] = std::move(vals[0]);
}
return {range_from_bytes(schema, pk_value)};
}
} // anonymous namespace
dht::partition_range_vector statement_restrictions::get_partition_key_ranges(const query_options& options) const {
if (_partition_range_restrictions.empty()) {
return {dht::partition_range::make_open_ended_both_sides()};
}
if (has_token(_partition_range_restrictions[0])) {
if (_partition_range_restrictions.size() != 1) {
on_internal_error(
rlogger,
format("Unexpected size of token restrictions: {}", _partition_range_restrictions.size()));
}
return partition_ranges_from_token(_partition_range_restrictions[0], options);
} else if (_partition_range_is_simple) {
// Special case to avoid extra allocations required for a Cartesian product.
return partition_ranges_from_EQs(_partition_range_restrictions, options, *_schema);
}
return partition_ranges_from_singles(_partition_range_restrictions, options, *_schema);
}
namespace {
using namespace expr;
clustering_key_prefix::prefix_equal_tri_compare get_unreversed_tri_compare(const schema& schema) {
clustering_key_prefix::prefix_equal_tri_compare cmp(schema);
std::vector<data_type> types = cmp.prefix_type->types();
for (auto& t : types) {
if (t->is_reversed()) {
t = t->underlying_type();
}
}
cmp.prefix_type = make_lw_shared<compound_type<allow_prefixes::yes>>(types);
return cmp;
}
/// True iff r1 start is strictly before r2 start.
bool starts_before_start(
const query::clustering_range& r1,
const query::clustering_range& r2,
const clustering_key_prefix::prefix_equal_tri_compare& cmp) {
if (!r2.start()) {
return false; // r2 start is -inf, nothing is before that.
}
if (!r1.start()) {
return true; // r1 start is -inf, while r2 start is finite.
}
const auto diff = cmp(r1.start()->value(), r2.start()->value());
if (diff < 0) { // r1 start is strictly before r2 start.
return true;
}
if (diff > 0) { // r1 start is strictly after r2 start.
return false;
}
const auto len1 = r1.start()->value().representation().size();
const auto len2 = r2.start()->value().representation().size();
if (len1 == len2) { // The values truly are equal.
return r1.start()->is_inclusive() && !r2.start()->is_inclusive();
} else if (len1 < len2) { // r1 start is a prefix of r2 start.
// (a)>=(1) starts before (a,b)>=(1,1), but (a)>(1) doesn't.
return r1.start()->is_inclusive();
} else { // r2 start is a prefix of r1 start.
// (a,b)>=(1,1) starts before (a)>(1) but after (a)>=(1).
return r2.start()->is_inclusive();
}
}
/// True iff r1 start is before (or identical as) r2 end.
bool starts_before_or_at_end(
const query::clustering_range& r1,
const query::clustering_range& r2,
const clustering_key_prefix::prefix_equal_tri_compare& cmp) {
if (!r1.start()) {
return true; // r1 start is -inf, must be before r2 end.
}
if (!r2.end()) {
return true; // r2 end is +inf, everything is before it.
}
const auto diff = cmp(r1.start()->value(), r2.end()->value());
if (diff < 0) { // r1 start is strictly before r2 end.
return true;
}
if (diff > 0) { // r1 start is strictly after r2 end.
return false;
}
const auto len1 = r1.start()->value().representation().size();
const auto len2 = r2.end()->value().representation().size();
if (len1 == len2) { // The values truly are equal.
return r1.start()->is_inclusive() && r2.end()->is_inclusive();
} else if (len1 < len2) { // r1 start is a prefix of r2 end.
// a>=(1) starts before (a,b)<=(1,1) ends, but (a)>(1) doesn't.
return r1.start()->is_inclusive();
} else { // r2 end is a prefix of r1 start.
// (a,b)>=(1,1) starts before (a)<=(1) ends but after (a)<(1) ends.
return r2.end()->is_inclusive();
}
}
/// True if r1 end is strictly before r2 end.
bool ends_before_end(
const query::clustering_range& r1,
const query::clustering_range& r2,
const clustering_key_prefix::prefix_equal_tri_compare& cmp) {
if (!r1.end()) {
return false; // r1 end is +inf, which is after everything.
}
if (!r2.end()) {
return true; // r2 end is +inf, while r1 end is finite.
}
const auto diff = cmp(r1.end()->value(), r2.end()->value());
if (diff < 0) { // r1 end is strictly before r2 end.
return true;
}
if (diff > 0) { // r1 end is strictly after r2 end.
return false;
}
const auto len1 = r1.end()->value().representation().size();
const auto len2 = r2.end()->value().representation().size();
if (len1 == len2) { // The values truly are equal.
return !r1.end()->is_inclusive() && r2.end()->is_inclusive();
} else if (len1 < len2) { // r1 end is a prefix of r2 end.
// (a)<(1) ends before (a,b)<=(1,1), but (a)<=(1) doesn't.
return !r1.end()->is_inclusive();
} else { // r2 end is a prefix of r1 end.
// (a,b)<=(1,1) ends before (a)<=(1) but after (a)<(1).
return r2.end()->is_inclusive();
}
}
/// Correct clustering_range intersection. See #8157.
std::optional<query::clustering_range> intersection(
const query::clustering_range& r1,
const query::clustering_range& r2,
const clustering_key_prefix::prefix_equal_tri_compare& cmp) {
// Assume r1's start is to the left of r2's start.
if (starts_before_start(r2, r1, cmp)) {
return intersection(r2, r1, cmp);
}
if (!starts_before_or_at_end(r2, r1, cmp)) {
return {};
}
const auto& intersection_start = r2.start();
const auto& intersection_end = ends_before_end(r1, r2, cmp) ? r1.end() : r2.end();
if (intersection_start == intersection_end && intersection_end.has_value()) {
return query::clustering_range::make_singular(intersection_end->value());
}
return query::clustering_range(intersection_start, intersection_end);
}
struct range_less {
const class schema& s;
clustering_key_prefix::less_compare cmp = clustering_key_prefix::less_compare(s);
bool operator()(const query::clustering_range& x, const query::clustering_range& y) const {
if (!x.start() && !y.start()) {
return false;
}
if (!x.start()) {
return true;
}
if (!y.start()) {
return false;
}
return cmp(x.start()->value(), y.start()->value());
}
};
/// An expression visitor that translates multi-column atoms into clustering ranges.
struct multi_column_range_accumulator {
const query_options& options;
const schema_ptr schema;
std::vector<query::clustering_range> ranges{query::clustering_range::make_open_ended_both_sides()};
const clustering_key_prefix::prefix_equal_tri_compare prefix3cmp = get_unreversed_tri_compare(*schema);
void operator()(const binary_operator& binop) {
if (is_compare(binop.op)) {
auto opt_values = expr::get_tuple_elements(expr::evaluate(binop.rhs, options));
auto& lhs = expr::as<tuple_constructor>(binop.lhs);
std::vector<managed_bytes> values(lhs.elements.size());
for (size_t i = 0; i < lhs.elements.size(); ++i) {
auto& col = expr::as<column_value>(lhs.elements.at(i));
values[i] = *statements::request_validations::check_not_null(
opt_values[i],
"Invalid null value in condition for column {}", col.col->name_as_text());
}
intersect_all(to_range(binop.op, clustering_key_prefix(std::move(values))));
} else if (binop.op == oper_t::IN) {
const expr::constant tup = expr::evaluate(binop.rhs, options);
statements::request_validations::check_false(tup.is_null(), "Invalid null value for IN restriction");
process_in_values(expr::get_list_of_tuples_elements(tup));
} else {
on_internal_error(rlogger, format("multi_column_range_accumulator: unexpected atom {}", binop));
}
}
void operator()(const conjunction& c) {
std::ranges::for_each(c.children, [this] (const expression& child) { expr::visit(*this, child); });
}
void operator()(const constant& v) {
std::optional<bool> bool_val = get_bool_value(v);
if (!bool_val.has_value()) {
on_internal_error(rlogger, "non-bool constant encountered outside binary operator");
}
if (*bool_val == false) {
ranges.clear();
}
}
void operator()(const column_value&) {
on_internal_error(rlogger, "Column encountered outside binary operator");
}
void operator()(const token&) {
on_internal_error(rlogger, "Token encountered outside binary operator");
}
void operator()(const unresolved_identifier&) {
on_internal_error(rlogger, "Unresolved identifier encountered outside binary operator");
}
void operator()(const column_mutation_attribute&) {
on_internal_error(rlogger, "writetime/ttl encountered outside binary operator");
}
void operator()(const function_call&) {
on_internal_error(rlogger, "function call encountered outside binary operator");
}
void operator()(const cast&) {
on_internal_error(rlogger, "typecast encountered outside binary operator");
}
void operator()(const field_selection&) {
on_internal_error(rlogger, "field selection encountered outside binary operator");
}
void operator()(const null&) {
on_internal_error(rlogger, "null encountered outside binary operator");
}
void operator()(const bind_variable&) {
on_internal_error(rlogger, "bind variable encountered outside binary operator");
}
void operator()(const untyped_constant&) {
on_internal_error(rlogger, "untyped constant encountered outside binary operator");
}
void operator()(const tuple_constructor&) {
on_internal_error(rlogger, "tuple constructor encountered outside binary operator");
}
void operator()(const collection_constructor&) {
on_internal_error(rlogger, "collection constructor encountered outside binary operator");
}
void operator()(const usertype_constructor&) {
on_internal_error(rlogger, "collection constructor encountered outside binary operator");
}
/// Intersects each range with v. If any intersection is empty, clears ranges.
void intersect_all(const query::clustering_range& v) {
for (auto& r : ranges) {
auto intrs = intersection(r, v, prefix3cmp);
if (!intrs) {
ranges.clear();
break;
}
r = *intrs;
}
}
template<std::ranges::range Range>
requires std::convertible_to<typename Range::value_type::value_type, managed_bytes_opt>
void process_in_values(Range in_values) {
if (ranges.empty()) {
return; // Shortcircuit an easy case.
}
std::set<query::clustering_range, range_less> new_ranges(range_less{*schema});
for (const auto& current_tuple : in_values) {
// Each IN value is like a separate EQ restriction ANDed to the existing state.
auto current_range = to_range(
oper_t::EQ, clustering_key_prefix::from_optional_exploded(*schema, current_tuple));
for (const auto& r : ranges) {
auto intrs = intersection(r, current_range, prefix3cmp);
if (intrs) {
new_ranges.insert(*intrs);
}
}
}
ranges.assign(new_ranges.cbegin(), new_ranges.cend());
}
};
/// Calculates clustering bounds for the multi-column case.
std::vector<query::clustering_range> get_multi_column_clustering_bounds(
const query_options& options,
schema_ptr schema,
const std::vector<expression>& multi_column_restrictions) {
multi_column_range_accumulator acc{options, schema};
for (const auto& restr : multi_column_restrictions) {
expr::visit(acc, restr);
}
return acc.ranges;
}
/// Reverses the range if the type is reversed. Why don't we have nonwrapping_interval::reverse()??
query::clustering_range reverse_if_reqd(query::clustering_range r, const abstract_type& t) {
return t.is_reversed() ? query::clustering_range(r.end(), r.start()) : std::move(r);
}
constexpr bool inclusive = true;
/// Calculates clustering bounds for the single-column case.
std::vector<query::clustering_range> get_single_column_clustering_bounds(
const query_options& options,
const schema& schema,
const std::vector<expression>& single_column_restrictions) {
const size_t size_limit =
options.get_cql_config().restrictions.clustering_key_restrictions_max_cartesian_product_size;
size_t product_size = 1;
std::vector<std::vector<managed_bytes>> prior_column_values; // Equality values of columns seen so far.
for (size_t i = 0; i < single_column_restrictions.size(); ++i) {
auto values = possible_lhs_values(
&schema.clustering_column_at(i), // This should be the LHS of restrictions[i].
single_column_restrictions[i],
options);
if (auto list = std::get_if<value_list>(&values)) {
if (list->empty()) { // Impossible condition -- no rows can possibly match.
return {};
}
prior_column_values.push_back(*list);
product_size *= list->size();
error_if_exceeds(product_size, size_limit);
} else if (auto last_range = std::get_if<nonwrapping_interval<managed_bytes>>(&values)) {
// Must be the last column in the prefix, since it's neither EQ nor IN.
std::vector<query::clustering_range> ck_ranges;
if (prior_column_values.empty()) {
// This is the first and last range; just turn it into a clustering_key_prefix.
ck_ranges.push_back(
reverse_if_reqd(
last_range->transform([] (const managed_bytes& val) { return clustering_key_prefix::from_range(std::array<managed_bytes, 1>{val}); }),
*schema.clustering_column_at(i).type));
} else {
// Prior clustering columns are equality-restricted (either via = or IN), producing one or more
// prior_column_values elements. Now we will turn each such element into a CK range dictated by those
// equalities and this inequality represented by last_range. Each CK range's upper/lower bound is
// formed by extending the Cartesian-product element with the corresponding last_range bound, if it
// exists; if it doesn't, the CK range bound is just the Cartesian-product element, inclusive.
//
// For example, the expression `c1=1 AND c2=2 AND c3>3` makes lower CK bound (1,2,3) exclusive and
// upper CK bound (1,2) inclusive.
ck_ranges.reserve(product_size);
const auto extra_lb = last_range->start(), extra_ub = last_range->end();
for (auto& b : cartesian_product(prior_column_values)) {
auto new_lb = b, new_ub = b;
if (extra_lb) {
new_lb.push_back(extra_lb->value());
}
if (extra_ub) {
new_ub.push_back(extra_ub->value());
}
query::clustering_range::bound new_start(new_lb, extra_lb ? extra_lb->is_inclusive() : inclusive);
query::clustering_range::bound new_end (new_ub, extra_ub ? extra_ub->is_inclusive() : inclusive);
ck_ranges.push_back(reverse_if_reqd({new_start, new_end}, *schema.clustering_column_at(i).type));
}
}
sort(ck_ranges.begin(), ck_ranges.end(), range_less{schema});
return ck_ranges;
}
}
// All prefix columns are restricted by EQ or IN. The resulting CK ranges are just singular ranges of corresponding
// prior_column_values.
std::vector<query::clustering_range> ck_ranges(product_size);
cartesian_product cp(prior_column_values);
std::transform(cp.begin(), cp.end(), ck_ranges.begin(), std::bind_front(query::clustering_range::make_singular));
sort(ck_ranges.begin(), ck_ranges.end(), range_less{schema});
return ck_ranges;
}
// In old v1 indexes the token column was of type blob.
// This causes problems because blobs are sorted differently than the bigint token values that they represent.
// Tokens are encoded as 8 byte big endian two's complement signed integers,
// which with blob sorting makes them ordered like this:
// 0, 1, 2, 3, 4, 5, ..., bigint_max, bigint_min, ...., -5, -4, -3, -2, -1
// Because of this clustering restrictions like token(p) > -4 and token(p) < 4 need to be translated
// to two clustering ranges on the old index.
// All binary_operators in token_restriction must have column_value{token_column} as their LHS.
static std::vector<query::clustering_range> get_index_v1_token_range_clustering_bounds(
const query_options& options,
const column_definition& token_column,
const expression& token_restriction) {
// A workaround in order to make possible_lhs_values work properly.
// possible_lhs_values looks at the column type and uses this type's comparator.
// This is a problem because when using blob's comparator, -4 is greater than 4.
// This makes possible_lhs_values think that an expression like token(p) > -4 and token(p) < 4
// is impossible to fulfill.
// Create a fake token column with the type set to bigint, translate the restriction to use this column
// and use this restriction to calculate possible lhs values.
column_definition token_column_bigint = token_column;
token_column_bigint.type = long_type;
expression new_token_restrictions = replace_column_def(token_restriction, &token_column_bigint);
std::variant<value_list, nonwrapping_range<managed_bytes>> values =
possible_lhs_values(&token_column_bigint, new_token_restrictions, options);
return std::visit(overloaded_functor {
[](const value_list& list) {
std::vector<query::clustering_range> ck_ranges;
ck_ranges.reserve(list.size());
for (auto&& value : list) {
ck_ranges.emplace_back(query::clustering_range::make_singular(std::vector<managed_bytes>{value}));
}
return ck_ranges;
},
[](const nonwrapping_interval<managed_bytes>& range) {
auto int64_from_be_bytes = [](const managed_bytes& int_bytes) -> int64_t {
if (int_bytes.size() != 8) {
throw std::runtime_error("token restriction value should be 8 bytes");
}
return read_be<int64_t>((const char*)&int_bytes[0]);
};
auto int64_to_be_bytes = [](int64_t int_val) -> managed_bytes {
managed_bytes int_bytes(managed_bytes::initialized_later{}, 8);
write_be((char*)&int_bytes[0], int_val);
return int_bytes;
};
int64_t token_low = std::numeric_limits<int64_t>::min();
int64_t token_high = std::numeric_limits<int64_t>::max();
bool low_inclusive = true, high_inclusive = true;
const std::optional<interval_bound<managed_bytes>>& start = range.start();
const std::optional<interval_bound<managed_bytes>>& end = range.end();
if (start.has_value()) {
token_low = int64_from_be_bytes(start->value());
low_inclusive = start->is_inclusive();
}
if (end.has_value()) {
token_high = int64_from_be_bytes(end->value());
high_inclusive = end->is_inclusive();
}
query::clustering_range::bound lower_bound(std::vector({int64_to_be_bytes(token_low)}), low_inclusive);
query::clustering_range::bound upper_bound(std::vector({int64_to_be_bytes(token_high)}), high_inclusive);
std::vector<query::clustering_range> ck_ranges;
if (token_high < token_low) {
// Impossible range, return empty clustering ranges
return ck_ranges;
}
// Blob encoded tokens are sorted like this:
// 0, 1, 2, 3, 4, 5, ..., bigint_max, bigint_min, ...., -5, -4, -3, -2, -1
// This means that in cases where low >= 0 or high < 0 we can simply use the whole range.
// In other cases we have to take two ranges: (low, -1] and [0, high).
if (token_low >= 0 || token_high < 0) {
ck_ranges.emplace_back(std::move(lower_bound), std::move(upper_bound));
} else {
query::clustering_range::bound zero_bound(std::vector({int64_to_be_bytes(0)}));
query::clustering_range::bound min1_bound(std::vector({int64_to_be_bytes(-1)}));
ck_ranges.reserve(2);
if (!(token_high == 0 && !high_inclusive)) {
ck_ranges.emplace_back(std::move(zero_bound), std::move(upper_bound));
}
if (!(token_low == -1 && !low_inclusive)) {
ck_ranges.emplace_back(std::move(lower_bound), std::move(min1_bound));
}
}
return ck_ranges;
}
}, values);
}
using opt_bound = std::optional<query::clustering_range::bound>;
/// Makes a partial bound out of whole_bound's prefix. If the partial bound is strictly shorter than the whole, it is
/// exclusive. Otherwise, it matches the whole_bound's inclusivity.
opt_bound make_prefix_bound(
size_t prefix_len, const std::vector<bytes>& whole_bound, bool whole_bound_is_inclusive) {
if (whole_bound.empty()) {
return {};
}
// Couldn't get std::ranges::subrange(whole_bound, prefix_len) to compile :(
std::vector<bytes> partial_bound(
whole_bound.cbegin(), whole_bound.cbegin() + std::min(prefix_len, whole_bound.size()));
return query::clustering_range::bound(
clustering_key_prefix(move(partial_bound)),
prefix_len >= whole_bound.size() && whole_bound_is_inclusive);
}
/// Given a multi-column range in CQL order, breaks it into an equivalent union of clustering-order ranges. Returns
/// those ranges as vector elements.
///
/// A difference between CQL order and clustering order means that the right-hand side of a clustering-key comparison is
/// not necessarily a single (lower or upper) bound on the clustering key in storage. Eg, `WITH CLUSTERING ORDER BY (a
/// ASC, b DESC)` indicates that "a less than 5" means "a comes before 5 in storage", but "b less than 5" means "b comes
/// AFTER 5 in storage". Therefore the CQL expression (a,b)<(5,5) cannot be executed by fetching a single range from
/// the storage layer -- the right-hand side is not a single upper bound from the storage layer's perspective.
///
/// When translating the WHERE clause into clustering ranges to fetch, it's natural to first calculate the CQL-order
/// ranges: comparisons define ranges, the AND operator intersects them, the IN operator makes a Cartesian product. The
/// result of this is a union of ranges in CQL order that define the clustering slice to fetch. And if the clustering
/// order is the same as the CQL order, these ranges can be sent to the storage proxy directly to fetch the correct
/// result. But if the two orders differ, there is some work to be done first. This is simple enough for ranges that
/// only vary a single column -- see reverse_if_reqd(). Multi-column ranges are more complicated; they are translated
/// into an equivalent union of clustering-order ranges by get_equivalent_ranges().
///
/// Continuing the above example, we can translate the CQL expression (a,b)<(5,5) into a union of several ranges that
/// are continuous in storage. We begin by observing that (a,b)<(5,5) is the same as a<5 OR (a=5 AND b<5). This is a
/// union of two ranges: the range corresponding to a<5, plus the range corresponding to (a=5 AND b<5). Note that both
/// of these ranges are continuous in storage because they only vary a single column:
///
/// * a<5 is a range from -inf to clustering_key_prefix(5) exclusive
///
/// * (a=5 AND b<5) is a range from clustering_key_prefix(5,5) exclusive to clustering_key_prefix(5) inclusive; note
/// the clustering order between those start/end bounds
///
/// Here is an illustration of those two ranges in storage, with rows represented vertically and clustering-ordered left
/// to right:
///
/// a: 4 4 4 4 4 4 5 5 5 5 5 5 5 5 6 6 6 6 6
/// b: 5 4 3 2 1 0 7 6 5 4 3 2 1 0 5 4 3 2 1
/// 1st range ^^^^^^^^^^^ ^^^^^^^^^ 2nd range
///
/// For more examples of this range translation, please see the statement_restrictions unit tests.
std::vector<query::clustering_range> get_equivalent_ranges(
const query::clustering_range& cql_order_range, const schema& schema) {
const auto& cql_lb = cql_order_range.start();
const auto& cql_ub = cql_order_range.end();
if (cql_lb == cql_ub && (!cql_lb || cql_lb->is_inclusive())) {
return {cql_order_range};
}
const auto cql_lb_bytes = cql_lb ? cql_lb->value().explode(schema) : std::vector<bytes>{};
const auto cql_ub_bytes = cql_ub ? cql_ub->value().explode(schema) : std::vector<bytes>{};
const bool cql_lb_is_inclusive = cql_lb ? cql_lb->is_inclusive() : false;
const bool cql_ub_is_inclusive = cql_ub ? cql_ub->is_inclusive() : false;
size_t common_prefix_len = 0;
// Skip equal values; they don't contribute to equivalent-range generation.
while (common_prefix_len < cql_lb_bytes.size() && common_prefix_len < cql_ub_bytes.size() &&
cql_lb_bytes[common_prefix_len] == cql_ub_bytes[common_prefix_len]) {
++common_prefix_len;
}
std::vector<query::clustering_range> ranges;
// First range is special: it has both bounds.
opt_bound lb1 = make_prefix_bound(
common_prefix_len + 1, cql_lb_bytes, cql_lb_is_inclusive);
opt_bound ub1 = make_prefix_bound(
common_prefix_len + 1, cql_ub_bytes, cql_ub_is_inclusive);
auto range1 = schema.clustering_column_at(common_prefix_len).type->is_reversed() ?
query::clustering_range(ub1, lb1) : query::clustering_range(lb1, ub1);
ranges.push_back(std::move(range1));
for (size_t p = common_prefix_len + 2; p <= cql_lb_bytes.size(); ++p) {
opt_bound lb = make_prefix_bound(p, cql_lb_bytes, cql_lb_is_inclusive);
opt_bound ub = make_prefix_bound(p - 1, cql_lb_bytes, /*irrelevant:*/true);
if (ub) {
ub = query::clustering_range::bound(ub->value(), inclusive);
}
auto range = schema.clustering_column_at(p - 1).type->is_reversed() ?
query::clustering_range(ub, lb) : query::clustering_range(lb, ub);
ranges.push_back(std::move(range));
}
for (size_t p = common_prefix_len + 2; p <= cql_ub_bytes.size(); ++p) {
// Note the difference from the cql_lb_bytes case above!
opt_bound ub = make_prefix_bound(p, cql_ub_bytes, cql_ub_is_inclusive);
opt_bound lb = make_prefix_bound(p - 1, cql_ub_bytes, /*irrelevant:*/true);
if (lb) {
lb = query::clustering_range::bound(lb->value(), inclusive);
}
auto range = schema.clustering_column_at(p - 1).type->is_reversed() ?
query::clustering_range(ub, lb) : query::clustering_range(lb, ub);
ranges.push_back(std::move(range));
}
return ranges;
}
/// Extracts raw multi-column bounds from exprs; last one wins.
query::clustering_range range_from_raw_bounds(
const std::vector<expression>& exprs, const query_options& options, const schema& schema) {
opt_bound lb, ub;
for (const auto& e : exprs) {
if (auto b = find_clustering_order(e)) {
expr::constant tup_val = expr::evaluate(b->rhs, options);
if (tup_val.is_null()) {
on_internal_error(rlogger, format("range_from_raw_bounds: unexpected atom {}", *b));
}
const auto r = to_range(
b->op, clustering_key_prefix::from_optional_exploded(schema, expr::get_tuple_elements(tup_val)));
if (r.start()) {
lb = r.start();
}
if (r.end()) {
ub = r.end();
}
}
}
return {lb, ub};
}
} // anonymous namespace
std::vector<query::clustering_range> statement_restrictions::get_clustering_bounds(const query_options& options) const {
if (_clustering_prefix_restrictions.empty()) {
return {query::clustering_range::make_open_ended_both_sides()};
}
if (find_binop(_clustering_prefix_restrictions[0], expr::is_multi_column)) {
bool all_natural = true, all_reverse = true; ///< Whether column types are reversed or natural.
for (auto& r : _clustering_prefix_restrictions) { // TODO: move to constructor, do only once.
using namespace expr;
const auto& binop = expr::as<binary_operator>(r);
if (is_clustering_order(binop)) {
return {range_from_raw_bounds(_clustering_prefix_restrictions, options, *_schema)};
}
for (auto& element : expr::as<tuple_constructor>(binop.lhs).elements) {
auto& cv = expr::as<column_value>(element);
if (cv.col->type->is_reversed()) {
all_natural = false;
} else {
all_reverse = false;
}
}
}
auto bounds = get_multi_column_clustering_bounds(options, _schema, _clustering_prefix_restrictions);
if (!all_natural && !all_reverse) {
std::vector<query::clustering_range> bounds_in_clustering_order;
for (const auto& b : bounds) {
const auto eqv = get_equivalent_ranges(b, *_schema);
bounds_in_clustering_order.insert(bounds_in_clustering_order.end(), eqv.cbegin(), eqv.cend());
}
return bounds_in_clustering_order;
}
if (all_reverse) {
for (auto& crange : bounds) {
crange = query::clustering_range(crange.end(), crange.start());
}
}
return bounds;
} else {
return get_single_column_clustering_bounds(options, *_schema, _clustering_prefix_restrictions);
}
}
namespace {
/// True iff get_partition_slice_for_global_index_posting_list() will be able to calculate the token value from the
/// given restrictions. Keep in sync with the get_partition_slice_for_global_index_posting_list() source.
bool token_known(const statement_restrictions& r) {
return !r.has_partition_key_unrestricted_components() && r.get_partition_key_restrictions()->is_all_eq();
}
} // anonymous namespace
bool statement_restrictions::need_filtering() const {
using namespace expr;
if (_uses_secondary_indexing && has_token(_partition_key_restrictions->expression)) {
// If there is a token(p1, p2) restriction, no p1, p2 restrictions are allowed in the query.
// All other restrictions must be on clustering or regular columns.
int64_t non_pk_restrictions_count = _clustering_columns_restrictions->size();
non_pk_restrictions_count += _nonprimary_key_restrictions->size();
// We are querying using an index, one restriction goes to the index restriction.
// If there are some restrictions other than token() and index column then we need to do filtering.
// p1, p2 can have many different values, so clustering prefix breaks.
return non_pk_restrictions_count > 1;
}
const auto npart = _partition_key_restrictions->size();
if (npart > 0 && npart < _schema->partition_key_size()) {
// Can't calculate the token value, so a naive base-table query must be filtered. Same for any index tables,
// except if there's only one restriction supported by an index.
return !(npart == 1 && _has_queriable_pk_index &&
_clustering_columns_restrictions->empty() && _nonprimary_key_restrictions->empty());
}
if (_partition_key_restrictions->needs_filtering(*_schema)) {
// We most likely cannot calculate token(s). Neither base-table nor index-table queries can avoid filtering.
return true;
}
// Now we know the partition key is either unrestricted or fully restricted.
const auto nreg = _nonprimary_key_restrictions->size();
if (nreg > 1 || (nreg == 1 && !_has_queriable_regular_index)) {
return true; // Regular columns are unsorted in storage and no single index suffices.
}
if (nreg == 1) { // Single non-key restriction supported by an index.
// Will the index-table query require filtering? That depends on whether its clustering key is restricted to a
// continuous range. Recall that this clustering key is (token, pk, ck) of the base table.
if (npart == 0 && _clustering_columns_restrictions->empty()) {
return false; // No clustering key restrictions => whole partitions.
}
return !token_known(*this) || _clustering_columns_restrictions->needs_filtering(*_schema)
// Multi-column restrictions don't require filtering when querying the base table, but the index
// table has a different clustering key and may require filtering.
|| _has_multi_column;
}
// Now we know there are no nonkey restrictions.
if (dynamic_pointer_cast<multi_column_restriction>(_clustering_columns_restrictions)) {
// Multicolumn bounds mean lexicographic order, implying a continuous clustering range. Multicolumn IN means a
// finite set of continuous ranges. Multicolumn restrictions cannot currently be combined with single-column
// clustering restrictions. Therefore, a continuous clustering range is guaranteed.
return false;
}
if (_has_queriable_ck_index && _uses_secondary_indexing) {
// In cases where we use an index, clustering column restrictions might cause the need for filtering.
// TODO: This is overly conservative, there are some cases when this returns true but filtering
// is not needed. Because of that the data_dictionary::database will sometimes perform filtering when it's not actually needed.
// Query performance shouldn't be affected much, at most we will filter rows that are all correct.
// Here are some cases to consider:
// On a table with primary key (p, c1, c2, c3) with an index on c3
// WHERE c3 = ? - doesn't require filtering
// WHERE c1 = ? AND c2 = ? AND c3 = ? - requires filtering
// WHERE p = ? AND c1 = ? AND c3 = ? - doesn't require filtering, but we conservatively report it does
// WHERE p = ? AND c1 LIKE ? AND c3 = ? - requires filtering
// WHERE p = ? AND c1 = ? AND c2 LIKE ? AND c3 = ? - requires filtering
// WHERE p = ? AND c1 = ? AND c2 = ? AND c3 = ? - doesn't use an index
// WHERE p = ? AND c1 = ? AND c2 < ? AND c3 = ? - doesn't require filtering, but we report it does
return _clustering_columns_restrictions->size() > 1;
}
// Now we know that the query doesn't use an index.
// The only thing that can cause filtering now are the clustering columns.
return _clustering_columns_restrictions->needs_filtering(*_schema);
}
void statement_restrictions::validate_secondary_index_selections(bool selects_only_static_columns) {
if (key_is_in_relation()) {
throw exceptions::invalid_request_exception(
"Select on indexed columns and with IN clause for the PRIMARY KEY are not supported");
}
}
const single_column_restrictions::restrictions_map& statement_restrictions::get_single_column_partition_key_restrictions() const {
static single_column_restrictions::restrictions_map empty;
auto single_restrictions = dynamic_pointer_cast<single_column_partition_key_restrictions>(_partition_key_restrictions);
if (!single_restrictions) {
if (dynamic_pointer_cast<initial_key_restrictions<partition_key>>(_partition_key_restrictions)) {
return empty;
}
throw std::runtime_error("statement restrictions for multi-column partition key restrictions are not implemented yet");
}
return single_restrictions->restrictions();
}
/**
* @return clustering key restrictions split into single column restrictions (e.g. for filtering support).
*/
const single_column_restrictions::restrictions_map& statement_restrictions::get_single_column_clustering_key_restrictions() const {
static single_column_restrictions::restrictions_map empty;
auto single_restrictions = dynamic_pointer_cast<single_column_clustering_key_restrictions>(_clustering_columns_restrictions);
if (!single_restrictions) {
if (dynamic_pointer_cast<initial_key_restrictions<clustering_key>>(_clustering_columns_restrictions)) {
return empty;
}
throw std::runtime_error("statement restrictions for multi-column partition key restrictions are not implemented yet");
}
return single_restrictions->restrictions();
}
void statement_restrictions::prepare_indexed_global(const schema& idx_tbl_schema) {
if (!_partition_range_is_simple) {
return;
}
const column_definition* token_column = &idx_tbl_schema.clustering_column_at(0);
if (has_token(_partition_key_restrictions->expression)) {
// When there is a token(p1, p2) >/</= ? restriction, it is not allowed to have restrictions on p1 or p2.
// This means that p1 and p2 can have many different values (token is a hash, can have collisions).
// Clustering prefix ends after token_restriction, all further restrictions have to be filtered.
expr::expression token_restriction = replace_token(_partition_key_restrictions->expression, token_column);
_idx_tbl_ck_prefix = std::vector{std::move(token_restriction)};
return;
}
// If we're here, it means the index cannot be on a partition column: process_partition_key_restrictions()
// avoids indexing when _partition_range_is_simple. See _idx_tbl_ck_prefix blurb for its composition.
_idx_tbl_ck_prefix = std::vector<expr::expression>(1 + _schema->partition_key_size());
_idx_tbl_ck_prefix->reserve(_idx_tbl_ck_prefix->size() + idx_tbl_schema.clustering_key_size());
for (const auto& e : _partition_range_restrictions) {
const auto col = expr::as<column_value>(find(e, oper_t::EQ)->lhs).col;
const auto pos = _schema->position(*col) + 1;
(*_idx_tbl_ck_prefix)[pos] = replace_column_def(e, &idx_tbl_schema.clustering_column_at(pos));
}
add_clustering_restrictions_to_idx_ck_prefix(idx_tbl_schema);
(*_idx_tbl_ck_prefix)[0] = binary_operator(
column_value(token_column),
oper_t::EQ,
// TODO: This should be a unique marker whose value we set at execution time. There is currently no
// handy mechanism for doing that in query_options.
expr::constant::make_unset_value(token_column->type));
}
void statement_restrictions::prepare_indexed_local(const schema& idx_tbl_schema) {
if (!_partition_range_is_simple) {
return;
}
// Local index clustering key is (indexed column, base clustering key)
_idx_tbl_ck_prefix = std::vector<expr::expression>();
_idx_tbl_ck_prefix->reserve(1 + _clustering_prefix_restrictions.size());
const column_definition& indexed_column = idx_tbl_schema.column_at(column_kind::clustering_key, 0);
const column_definition& indexed_column_base_schema = *_schema->get_column_definition(indexed_column.name());
// Find index column restrictions in the WHERE clause
std::vector<expr::expression> idx_col_restrictions =
extract_single_column_restrictions_for_column(*_where, indexed_column_base_schema);
expr::expression idx_col_restriction_expr = expr::expression(expr::conjunction{std::move(idx_col_restrictions)});
// Translate the restriction to use column from the index schema and add it
expr::expression replaced_idx_restriction = replace_column_def(idx_col_restriction_expr, &indexed_column);
_idx_tbl_ck_prefix->push_back(replaced_idx_restriction);
// Add restrictions for the clustering key
add_clustering_restrictions_to_idx_ck_prefix(idx_tbl_schema);
}
void statement_restrictions::add_clustering_restrictions_to_idx_ck_prefix(const schema& idx_tbl_schema) {
for (const auto& e : _clustering_prefix_restrictions) {
if (find_binop(_clustering_prefix_restrictions[0], expr::is_multi_column)) {
// TODO: We could handle single-element tuples, eg. `(c)>=(123)`.
break;
}
const auto any_binop = find_binop(e, [] (auto&&) { return true; });
if (!any_binop) {
break;
}
const auto col = expr::as<column_value>(any_binop->lhs).col;
_idx_tbl_ck_prefix->push_back(replace_column_def(e, idx_tbl_schema.get_column_definition(col->name())));
}
}
std::vector<query::clustering_range> statement_restrictions::get_global_index_clustering_ranges(
const query_options& options,
const schema& idx_tbl_schema) const {
if (!_idx_tbl_ck_prefix) {
on_internal_error(
rlogger, "statement_restrictions::get_global_index_clustering_ranges called with unprepared index");
}
std::vector<managed_bytes> pk_value(_schema->partition_key_size());
for (const auto& e : _partition_range_restrictions) {
const auto col = expr::as<column_value>(find(e, oper_t::EQ)->lhs).col;
const auto vals = std::get<value_list>(possible_lhs_values(col, e, options));
if (vals.empty()) { // Case of C=1 AND C=2.
return {};
}
pk_value[_schema->position(*col)] = std::move(vals[0]);
}
std::vector<bytes> pkv_linearized(pk_value.size());
std::transform(pk_value.cbegin(), pk_value.cend(), pkv_linearized.begin(),
[] (const managed_bytes& mb) { return to_bytes(mb); });
auto& token_column = idx_tbl_schema.clustering_column_at(0);
bytes_opt token_bytes = token_column.get_computation().compute_value(
*_schema, pkv_linearized, clustering_row(clustering_key_prefix::make_empty()));
if (!token_bytes) {
on_internal_error(rlogger,
format("null value for token column in indexing table {}",
token_column.name_as_text()));
}
// WARNING: We must not yield to another fiber from here until the function's end, lest this RHS be
// overwritten.
const_cast<expr::expression&>(expr::as<binary_operator>((*_idx_tbl_ck_prefix)[0]).rhs) =
expr::constant(raw_value::make_value(*token_bytes), token_column.type);
// Multi column restrictions are not added to _idx_tbl_ck_prefix, they are handled later by filtering.
return get_single_column_clustering_bounds(options, idx_tbl_schema, *_idx_tbl_ck_prefix);
}
std::vector<query::clustering_range> statement_restrictions::get_global_index_token_clustering_ranges(
const query_options& options,
const schema& idx_tbl_schema
) const {
if (!_idx_tbl_ck_prefix.has_value()) {
on_internal_error(
rlogger, "statement_restrictions::get_global_index_token_clustering_ranges called with unprepared index");
}
const column_definition& token_column = idx_tbl_schema.clustering_column_at(0);
// In old indexes the token column was of type blob.
// This causes problems with sorting and must be handled separately.
if (token_column.type != long_type) {
return get_index_v1_token_range_clustering_bounds(options, token_column, _idx_tbl_ck_prefix->at(0));
}
return get_single_column_clustering_bounds(options, idx_tbl_schema, *_idx_tbl_ck_prefix);
}
std::vector<query::clustering_range> statement_restrictions::get_local_index_clustering_ranges(
const query_options& options,
const schema& idx_tbl_schema) const {
if (!_idx_tbl_ck_prefix.has_value()) {
on_internal_error(
rlogger, "statement_restrictions::get_local_index_clustering_ranges called with unprepared index");
}
// Multi column restrictions are not added to _idx_tbl_ck_prefix, they are handled later by filtering.
return get_single_column_clustering_bounds(options, idx_tbl_schema, *_idx_tbl_ck_prefix);
}
sstring statement_restrictions::to_string() const {
return _where ? expr::to_string(*_where) : "";
}
static bool has_eq_null(const query_options& options, const expression& expr) {
return find_binop(expr, [&] (const binary_operator& binop) {
return binop.op == oper_t::EQ && evaluate(binop.rhs, options).is_null();
});
}
bool statement_restrictions::range_or_slice_eq_null(const query_options& options) const {
return boost::algorithm::any_of(_partition_range_restrictions, std::bind_front(has_eq_null, options))
|| boost::algorithm::any_of(_clustering_prefix_restrictions, std::bind_front(has_eq_null, options));
}
} // namespace restrictions
} // namespace cql3