ClickHouse/src/Dictionaries/PostgreSQLDictionarySource.h
2021-06-10 23:34:27 +03:00

77 lines
2.2 KiB
C++

#pragma once
#if !defined(ARCADIA_BUILD)
#include "config_core.h"
#endif
#include "DictionaryStructure.h"
#include "IDictionarySource.h"
#if USE_LIBPQXX
#include "ExternalQueryBuilder.h"
#include <Core/Block.h>
#include <common/LocalDateTime.h>
#include <common/logger_useful.h>
#include <Storages/PostgreSQL/PoolWithFailover.h>
#include <pqxx/pqxx>
namespace DB
{
/// Allows loading dictionaries from a PostgreSQL database
class PostgreSQLDictionarySource final : public IDictionarySource
{
public:
struct Configuration
{
const String db;
const String schema;
const String table;
const String where;
const String invalidate_query;
const String update_field;
const UInt64 update_lag;
};
PostgreSQLDictionarySource(
const DictionaryStructure & dict_struct_,
const Configuration & configuration_,
postgres::PoolWithFailoverPtr pool_,
const Block & sample_block_);
/// copy-constructor is provided in order to support cloneability
PostgreSQLDictionarySource(const PostgreSQLDictionarySource & other);
PostgreSQLDictionarySource & operator=(const PostgreSQLDictionarySource &) = delete;
BlockInputStreamPtr loadAll() override;
BlockInputStreamPtr loadUpdatedAll() override;
BlockInputStreamPtr loadIds(const std::vector<UInt64> & ids) override;
BlockInputStreamPtr loadKeys(const Columns & key_columns, const std::vector<size_t> & requested_rows) override;
bool isModified() const override;
bool supportsSelectiveLoad() const override;
bool hasUpdateField() const override;
DictionarySourcePtr clone() const override;
std::string toString() const override;
private:
String getUpdateFieldAndDate();
String doInvalidateQuery(const std::string & request) const;
BlockInputStreamPtr loadBase(const String & query);
const DictionaryStructure dict_struct;
const Configuration configuration;
postgres::PoolWithFailoverPtr pool;
Block sample_block;
Poco::Logger * log;
ExternalQueryBuilder query_builder;
const std::string load_all_query;
std::chrono::time_point<std::chrono::system_clock> update_time;
mutable std::string invalidate_query_response;
};
}
#endif