dds::sub::Query Class Reference

<<value-type>> Encapsulates a query for a dds::sub::cond::QueryCondition. More...

#include <dds/sub/Query.hpp>

Public Member Functions
template<typename T >
	Query (const dds::sub::DataReader< T > &reader, const std::string &query_expression)
	Creates a query. More...
template<typename T , typename FWIterator >
	Query (const dds::sub::DataReader< T > &reader, const std::string &query_expression, const FWIterator &params_begin, const FWIterator &params_end)
	Creates a query with the expression parameters in an iterator range. More...
template<typename T >
	Query (const dds::sub::DataReader< T > &reader, const std::string &query_expression, const std::vector< std::string > &params)
	Creates a query with the expression parameters in a vector. More...
const std::string &	expression () const
	Gets the expression. More...
const_iterator	begin () const
	Provides the begin iterator to the parameter list. More...
const_iterator	end () const
	Provides the end iterator to the parameter list. More...
iterator	begin ()
	Provides the begin iterator to the parameter list. More...
iterator	end ()
	Provides the end iterator to the parameter list. More...
template<typename FWIterator >
void	parameters (const FWIterator &the_begin, const FWIterator the_end)
	Sets the parameters for the expression. More...
void	add_parameter (const std::string &param)
	Appends a parameter. More...
size_t	parameters_length () const
	Gets the number of parameters. More...
const std::vector< std::string > &	parameters () const
	<<extension>> Gets the parameters More...
std::string	name () const
	<<extension>> Gets the filter name More...
dds::sub::Query &	name (const std::string &the_name)
	<<extension>> Sets a filter name More...
const AnyDataReader &	data_reader () const
	Gets the related DataReader. More...

Detailed Description

<<value-type>> Encapsulates a query for a dds::sub::cond::QueryCondition.

A query contains the DataReader to query data from, an expression and optionally a list of parameters.

Queries and Filters Syntax defines the syntax of the expression and the parameters.

See also

Filtering with Query Conditions

Constructor & Destructor Documentation

Query() [1/3]

template<typename T >

dds::sub::Query::Query ( const dds::sub::DataReader< T > &  reader, const std::string &  query_expression  )

inline

Creates a query.

Template Parameters

T	The topic-type of the DataReader

Parameters

reader	DataReader to query data from
query_expression	Expression describing the query

Query() [2/3]

template<typename T , typename FWIterator >

dds::sub::Query::Query ( const dds::sub::DataReader< T > &  reader, const std::string &  query_expression, const FWIterator &  params_begin, const FWIterator &  params_end  )

inline

Creates a query with the expression parameters in an iterator range.

Template Parameters

T	The topic-type of the DataReader
FWIterator	A forward iterator whose value type is std::string (or convertible to std::string)

Parameters

reader	DataReader to query data from
query_expression	Expression describing the query
params_begin	The beginning of a range of parameters for the query expression
params_end	The end of the range

Query() [3/3]

template<typename T >

dds::sub::Query::Query ( const dds::sub::DataReader< T > &  reader, const std::string &  query_expression, const std::vector< std::string > &  params  )

inline

Creates a query with the expression parameters in a vector.

Template Parameters

T	The topic-type of the DataReader

Parameters

reader	DataReader to query data from
query_expression	Expression describing the query
params	The parameters for the query expression

Member Function Documentation

expression()

const std::string& dds::sub::Query::expression ( ) const

inline

Gets the expression.

begin() [1/2]

const_iterator dds::sub::Query::begin ( ) const

inline

Provides the begin iterator to the parameter list.

Returns

A random-access iterator whose value type is std::string

end() [1/2]

const_iterator dds::sub::Query::end ( ) const

inline

Provides the end iterator to the parameter list.

Returns

A random-access iterator whose value type is std::string

begin() [2/2]

iterator dds::sub::Query::begin ( )

inline

Provides the begin iterator to the parameter list.

Returns

A random-access iterator whose value type is std::string

end() [2/2]

iterator dds::sub::Query::end ( )

inline

Provides the end iterator to the parameter list.

Returns

A random-access iterator whose value type is std::string

parameters() [1/2]

template<typename FWIterator >

void dds::sub::Query::parameters ( const FWIterator &  the_begin, const FWIterator  the_end  )

inline

Sets the parameters for the expression.

Template Parameters

FWIterator

A forward iterator whose value type is std::string (or convertible to std::string)

Parameters

the_begin	The beginning of a range of parameters for the query expression
the_end	The end of the range

add_parameter()

void dds::sub::Query::add_parameter ( const std::string &  param )

inline

Appends a parameter.

parameters_length()

size_t dds::sub::Query::parameters_length ( ) const

inline

Gets the number of parameters.

parameters() [2/2]

const std::vector<std::string>& dds::sub::Query::parameters

(

)

const

<<extension>> Gets the parameters

name() [1/2]

std::string dds::sub::Query::name

(

)

const

<<extension>> Gets the filter name

Returns

The name of the filter, or an empty string when using the default SQL filter.

name() [2/2]

dds::sub::Query& dds::sub::Query::name

(

const std::string &

the_name

)

<<extension>> Sets a filter name

You can use one of the built-in filters (rti::topic::sql_filter_name and rti::topic::stringmatch_filter_name), or a custom filter, which you need to register using dds::domain::DomainParticipant::register_contentfilter().

[default] Empty string (equivalent to rti::topic::sql_filter_name)

data_reader()

const AnyDataReader& dds::sub::Query::data_reader ( ) const

inline

Gets the related DataReader.