storages::clickhouse::Cluster Class Reference

Table of Contents

• Classes
• Public Member Functions
• Detailed Description
• Constructor & Destructor Documentation
• Cluster()
• Member Function Documentation
• Execute() [1/2]
• Execute() [2/2]
• Insert() [1/2]
• Insert() [2/2]
• InsertRows() [1/2]
• InsertRows() [2/2]

Interface for executing queries on a cluster of ClickHouse servers. More...

#include <userver/storages/clickhouse/cluster.hpp>

Classes
class	NoAvailablePoolError
	Exception that is thrown if all specified endpoints are unavailable. More...

Public Member Functions
	Cluster (clients::dns::Resolver &resolver, const impl::ClickhouseSettings &settings, const components::ComponentConfig &config)
	~Cluster ()
	Cluster destructor.
	Cluster (const Cluster &)=delete
template<typename... Args>
ExecutionResult	Execute (const Query &query, const Args &... args) const
	Execute a statement at some host of the cluster with args as query parameters.
template<typename... Args>
ExecutionResult	Execute (OptionalCommandControl, const Query &query, const Args &... args) const
	Execute a statement with specified command control settings at some host of the cluster with args as query parameters.
template<typename T >
void	Insert (const std::string &table_name, const std::vector< std::string_view > &column_names, const T &data) const
	Insert data at some host of the cluster; T is expected to be a struct of vectors of same length.
template<typename T >
void	Insert (OptionalCommandControl, const std::string &table_name, const std::vector< std::string_view > &column_names, const T &data) const
	Insert data with specified command control settings at some host of the cluster; T is expected to be a struct of vectors of same length.
template<typename Container >
void	InsertRows (const std::string &table_name, const std::vector< std::string_view > &column_names, const Container &data) const
	Insert data at some host of the cluster; Container is expected to be an iterable of clickhouse-mapped type.
template<typename Container >
void	InsertRows (OptionalCommandControl, const std::string &table_name, const std::vector< std::string_view > &column_names, const Container &data) const
	Insert data with specified command control settings at some host of the cluster; Container is expected to be an iterable of clickhouse-mapped type.
void	WriteStatistics (::utils::statistics::Writer &writer) const
	Write cluster statistics.

Detailed Description

Interface for executing queries on a cluster of ClickHouse servers.

Usually retrieved from components::ClickHouse component.

Definition at line 36 of file cluster.hpp.

Constructor & Destructor Documentation

Cluster()

storages::clickhouse::Cluster::Cluster	(	clients::dns::Resolver &	resolver,
		const impl::ClickhouseSettings &	settings,
		const components::ComponentConfig &	config
	)

Cluster constructor

Parameters

resolver	asynchronous DNS resolver
settings	struct with settings fields: endpoints - list of endpoints (host + port) auth_settings - authentication settings (user, password, database)
config	components::ClickHouse component config

Member Function Documentation

Execute() [1/2]

template<typename... Args>

ExecutionResult storages::clickhouse::Cluster::Execute	(	const Query &	query,
		const Args &...	args
	)		const

Execute a statement at some host of the cluster with args as query parameters.

Definition at line 179 of file cluster.hpp.

Execute() [2/2]

template<typename... Args>

ExecutionResult storages::clickhouse::Cluster::Execute	(	OptionalCommandControl	optional_cc,
		const Query &	query,
		const Args &...	args
	)		const

Execute a statement with specified command control settings at some host of the cluster with args as query parameters.

Definition at line 185 of file cluster.hpp.

Insert() [1/2]

template<typename T >

void storages::clickhouse::Cluster::Insert	(	const std::string &	table_name,
		const std::vector< std::string_view > &	column_names,
		const T &	data
	)		const

Insert data at some host of the cluster; T is expected to be a struct of vectors of same length.

Parameters

table_name	table to insert into
column_names	names of columns of the table
data	data to insert See clickhouse_io for better understanding of T's requirements.

Definition at line 141 of file cluster.hpp.

Insert() [2/2]

template<typename T >

void storages::clickhouse::Cluster::Insert	(	OptionalCommandControl	optional_cc,
		const std::string &	table_name,
		const std::vector< std::string_view > &	column_names,
		const T &	data
	)		const

Insert data with specified command control settings at some host of the cluster; T is expected to be a struct of vectors of same length.

Parameters

table_name	table to insert into
column_names	names of columns of the table
data	data to insert See clickhouse_io for better understanding of T's requirements.

Definition at line 148 of file cluster.hpp.

InsertRows() [1/2]

template<typename Container >

void storages::clickhouse::Cluster::InsertRows	(	const std::string &	table_name,
		const std::vector< std::string_view > &	column_names,
		const Container &	data
	)		const

Insert data at some host of the cluster; Container is expected to be an iterable of clickhouse-mapped type.

Parameters

table_name	table to insert into
column_names	names of columns of the table
data	data to insert See clickhouse_io for better understanding of Container::value_type's requirements.

Note

This version of insert is less performant than Insert (it makes 2 copies of data instead of just 1 copy) due to implementation details, so consider using less convenient but more performant analogue if performance is a concern.

Definition at line 159 of file cluster.hpp.

InsertRows() [2/2]

template<typename Container >

void storages::clickhouse::Cluster::InsertRows	(	OptionalCommandControl	optional_cc,
		const std::string &	table_name,
		const std::vector< std::string_view > &	column_names,
		const Container &	data
	)		const

Insert data with specified command control settings at some host of the cluster; Container is expected to be an iterable of clickhouse-mapped type.

Parameters

table_name	table to insert into
column_names	names of columns of the table
data	data to insert See clickhouse_io for better understanding of Container::value_type's requirements.

Note

This version of insert is less performant than Insert (it makes 2 copies of data instead of just 1 copy) due to implementation details, so consider using less convenient but more performant analogue if performance is a concern.

Definition at line 166 of file cluster.hpp.

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The documentation for this class was generated from the following file:

• userver/storages/clickhouse/cluster.hpp