Files
scylladb/cql3/prepare_context.hh
Jan Ciolek e458340821 cql3: Remove term
term isn't used anywhere now. We can remove it and all classes that derive from it.

Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
2021-11-04 15:56:45 +01:00

115 lines
4.0 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-present 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/>.
*/
#pragma once
#include <seastar/core/shared_ptr.hh>
#include "seastarx.hh"
#include <optional>
#include <vector>
#include <stddef.h>
#include "cql3/expr/expression.hh"
class schema;
namespace cql3 {
class column_identifier;
class column_specification;
namespace functions { class function_call; }
/**
* Metadata class currently holding bind variables specifications and
* `function_call` AST nodes inside a query partition key restrictions.
* Populated and maintained at "prepare" step of query execution.
*/
class prepare_context final {
private:
std::vector<shared_ptr<column_identifier>> _variable_names;
std::vector<lw_shared_ptr<column_specification>> _specs;
std::vector<lw_shared_ptr<column_specification>> _target_columns;
// A list of pointers to prepared `function_call` cache ids, that
// participate in partition key ranges computation within an LWT statement.
std::vector<::shared_ptr<std::optional<uint8_t>>> _pk_function_calls_cache_ids;
// The flag denoting whether the context is currently in partition key
// processing mode (inside query restrictions AST nodes). If set to true,
// then every `function_call` instance will be recorded in the context and
// will be assigned an identifier, which will then be used for caching
// the function call results.
bool _processing_pk_restrictions = false;
public:
prepare_context() = default;
size_t bound_variables_size() const;
const std::vector<lw_shared_ptr<column_specification>>& get_variable_specifications() const &;
std::vector<lw_shared_ptr<column_specification>> get_variable_specifications() &&;
std::vector<uint16_t> get_partition_key_bind_indexes(const schema& schema) const;
void add_variable_specification(int32_t bind_index, lw_shared_ptr<column_specification> spec);
void set_bound_variables(const std::vector<shared_ptr<column_identifier>>& prepare_meta);
void clear_pk_function_calls_cache();
// Record a new function call, which evaluates a partition key constraint.
// Also automatically assigns an id to the AST node for caching purposes.
void add_pk_function_call(cql3::expr::function_call& fn);
// Inform the context object that it has started or ended processing the
// partition key part of statement restrictions.
void set_processing_pk_restrictions(bool flag) noexcept {
_processing_pk_restrictions = flag;
}
bool is_processing_pk_restrictions() const noexcept {
return _processing_pk_restrictions;
}
};
}