#include <userver/storages/postgres/options.hpp>

Detailed Description

A structure to control timeouts for PosrgreSQL queries

There are two parameters, execute and statement.

execute parameter controls the overall time the driver spends executing a query, that includes:

connecting to PostgreSQL server, if there are no connections available and connection pool still has space for new connections;
waiting for a connection to become idle if there are no idle connections and connection pool already has reached it's max size;
preparing a statement if the statement is run for the first time on the connection;
binding parameters and executing the statement;
waiting for the first results to arrive from the server. If the result set is big, only time to the first data packet is taken into account.

statement is rather straightforward, it's the PostgreSQL server-side parameter, and it controls the time the database backend can spend executing a single statement. It is very costly to change the statement timeout often, as it requires a roundtrip to the database to change the setting.

See also: https://www.postgresql.org/docs/12/runtime-config-client.html

execute timeout should always be greater than the statement timeout!

In case of a timeout, either back-end or overall, the client gets an exception and the driver tries to clean up the connection for further reuse.

Examples: postgresql/functional_tests/basic_chaos/postgres_service.cpp.

Definition at line 111 of file options.hpp.

Public Member Functions
constexpr	CommandControl (TimeoutDuration execute, TimeoutDuration statement)

constexpr CommandControl	WithExecuteTimeout (TimeoutDuration n) const noexcept

constexpr CommandControl	WithStatementTimeout (TimeoutDuration s) const noexcept

bool	operator== (const CommandControl &rhs) const

bool	operator!= (const CommandControl &rhs) const

Public Attributes
TimeoutDuration	execute {}
	Overall timeout for a command being executed.

TimeoutDuration	statement {}
	PostgreSQL server-side timeout.

Constructor & Destructor Documentation

◆ CommandControl()

constexpr storages::postgres::CommandControl::CommandControl	(	TimeoutDuration	execute,
		TimeoutDuration	statement )

inlineconstexpr

Definition at line 117 of file options.hpp.

Member Function Documentation

◆ operator!=()

bool storages::postgres::CommandControl::operator!= ( const CommandControl & rhs ) const

inline

Definition at line 134 of file options.hpp.

◆ operator==()

bool storages::postgres::CommandControl::operator== ( const CommandControl & rhs ) const

inline

Definition at line 130 of file options.hpp.

◆ WithExecuteTimeout()

constexpr CommandControl storages::postgres::CommandControl::WithExecuteTimeout ( TimeoutDuration n ) const

inlineconstexprnoexcept

Definition at line 120 of file options.hpp.

◆ WithStatementTimeout()

constexpr CommandControl storages::postgres::CommandControl::WithStatementTimeout ( TimeoutDuration s ) const

inlineconstexprnoexcept

Definition at line 125 of file options.hpp.

Member Data Documentation

◆ execute

TimeoutDuration storages::postgres::CommandControl::execute {}

Overall timeout for a command being executed.

Definition at line 113 of file options.hpp.

◆ statement

TimeoutDuration storages::postgres::CommandControl::statement {}

PostgreSQL server-side timeout.

Definition at line 115 of file options.hpp.

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

userver/storages/postgres/options.hpp