libdballe 9.6
Public Member Functions | List of all members
dballe::Cursor Class Referenceabstract

Base class for cursors that iterate over DB query results. More...

#include <cursor.h>

Inheritance diagram for dballe::Cursor:
dballe::CursorData dballe::CursorMessage dballe::CursorStation dballe::CursorStationData dballe::CursorSummary dballe::impl::CursorData dballe::impl::CursorMessage dballe::impl::CursorStation dballe::impl::CursorStationData dballe::impl::CursorSummary dballe::db::CursorData dballe::impl::msg::CursorData dballe::db::CursorStation dballe::impl::msg::CursorStation dballe::db::CursorStationData dballe::impl::msg::CursorStationData dballe::db::CursorSummary dballe::db::summary::Cursor< Station >

Public Member Functions

virtual bool has_value () const =0
 Check if the cursor points to a valid value.
 
virtual int remaining () const =0
 Get the number of rows still to be fetched.
 
virtual bool next ()=0
 Get a new item from the results of a query.
 
virtual void discard ()=0
 Discard the results that have not been read yet.
 
virtual DBStation get_station () const =0
 Get the whole station data in a single call.
 

Detailed Description

Base class for cursors that iterate over DB query results.

Member Function Documentation

◆ discard()

virtual void dballe::Cursor::discard ( )
pure virtual

◆ get_station()

virtual DBStation dballe::Cursor::get_station ( ) const
pure virtual

◆ has_value()

virtual bool dballe::Cursor::has_value ( ) const
pure virtual

Check if the cursor points to a valid value.

Returns
true if the cursor points to a valid accessible value, false if next() has not been called yet, or if at the end of iteration (i.e. next() returned false)

Implemented in dballe::db::summary::Cursor< Station >, dballe::impl::msg::CursorStation, dballe::impl::msg::CursorStationData, and dballe::impl::msg::CursorData.

◆ next()

virtual bool dballe::Cursor::next ( )
pure virtual

Get a new item from the results of a query.

Returns
true if a new record has been read, false if there is no more data to read

Implemented in dballe::db::summary::Cursor< Station >, dballe::impl::msg::CursorStation, dballe::impl::msg::CursorStationData, and dballe::impl::msg::CursorData.

◆ remaining()

virtual int dballe::Cursor::remaining ( ) const
pure virtual

Get the number of rows still to be fetched.

Returns
The number of rows still to be queried. The value is undefined if no query has been successfully peformed yet using this cursor.

Implemented in dballe::db::summary::Cursor< Station >, dballe::impl::msg::CursorStation, dballe::impl::msg::CursorStationData, and dballe::impl::msg::CursorData.


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