tip::db::pg::query Class Reference

Asynchronous query class. More...

#include <query.hpp>

Public Member Functions
	query (dbalias const &alias, std::string const &expression)
	Construct a query. More...
template<typename... T>
	query (dbalias const &alias, std::string const &expression, T const &...params)
	Construct a prepared query with params to bind. More...
	query (transaction_ptr tran, std::string const &expression)
	Construct a query. More...
template<typename... T>
	query (transaction_ptr tran, std::string const &expression, T const &...params)
	Construct a prepared query with params to bind. More...
template<typename... T>
query &	bind (T const &...params)
	Bind parameters for the query. More...
query &	bind ()
	Mark the query as prepared statement. More...
void	run_async (query_result_callback const &result, error_callback const &error) const
	Start running the query. More...
void	operator() (query_result_callback const &result, error_callback const &error) const

Detailed Description

Asynchronous query class.

Synopsis:

// Simple query
query (alias, "select * from pg_catalog.pg_tables")
([](result_ptr res, bool complete)
   {
       // process the query results
   },
   [](boost::system::error_code ec)
   {
       // handle the error here
   });
   // Extended query
   query (alias, "select * from pg_catalog.pg_type where typelem = $1", 26)
   ([](result_ptr res, bool complete)
   {
       // process the query results
   },
   [](boost::system::error_code ec)
   {
       // handle the error here
   });

See Also

Running queries

Processing query results

Definition at line 51 of file query.hpp.

Constructor & Destructor Documentation

tip::db::pg::query::query	(	dbalias const &	alias,
		std::string const &	expression
	)

Construct a query.

Query will start a transaction in a connection with the alias.

Parameters

alias	Database connection alias.
expression	SQL query expression

template<typename... T>

tip::db::pg::query::query	(	dbalias const &	alias,
		std::string const &	expression,
		T const &...	params
	)

Construct a prepared query with params to bind.

Query will start a transaction in a connection with the alias.

Parameters

alias	database alias
expression	SQL query expression
params	parameters to bind

Template Parameters

T	query parameter types

Definition at line 305 of file query.inl.

tip::db::pg::query::query	(	transaction_ptr	tran,
		std::string const &	expression
	)

Construct a query.

Precondition

Transaction must be started with a db_service::begin or another query.

Parameters

tran	transaction object pointer
expression	SQL query expression

template<typename... T>

tip::db::pg::query::query	(	transaction_ptr	tran,
		std::string const &	expression,
		T const &...	params
	)

Construct a prepared query with params to bind.

Precondition

Transaction must be started with a db_service::begin or another query.

Parameters

tran	transaction object pointer
expression	SQL query expression
params	parameters to bind

Template Parameters

T	query parameter types

Definition at line 312 of file query.inl.

Member Function Documentation

template<typename... T>

query & tip::db::pg::query::bind

(

T const &...

params

)

Bind parameters for the query.

Precondition

Query constructed

Parameters

params

prepared query parameters

Template Parameters

T	query parameter types

Definition at line 343 of file query.inl.

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query& tip::db::pg::query::bind

(

)

Mark the query as prepared statement.

void tip::db::pg::query::operator()	(	query_result_callback const &	result,
		error_callback const &	error
	)		const

Shortcut for tip::db::pg::query::run_async

Parameters

result	result callback
error	error callback

void tip::db::pg::query::run_async	(	query_result_callback const &	result,
		error_callback const &	error
	)		const

Start running the query.

Precondition

If a query was constructed with an alias - the database connection with the alias must be registered with the database service.

Query has been constructed and parameters bound.

Parameters

result	result callback
error	error callback

See Also

Callback types

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

• tip/db/pg/query.hpp
• tip/db/pg/query.inl