classxapian_1_1database.tex

xapian 是一个“Xapian 是一个开源概率论信息检索库

\index{Xapian::Database@{Xapian::Database}!get_collection_freq@{get\_\-collection\_\-freq}}
\index{get_collection_freq@{get\_\-collection\_\-freq}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-collection\_\-freq]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{types_8h_6979d98ebbe67186bd31e5ee2a7585cb}{Xapian::termcount} Xapian::Database::get\_\-collection\_\-freq (const std::string \& {\em tname}) const}}
\label{classXapian_1_1Database_eb8b2a78e6a7834bf0cc9e863bcfb95b}


Return the total number of occurrences of the given term. 

This is the sum of the number of ocurrences of the term in each document it indexes: ie, the sum of the within document frequencies of the term.

\begin{Desc}
\item[Parameters:]
\begin{description}
\item[{\em tname}]The term whose collection frequency is being requested. \end{description}
\end{Desc}
\hypertarget{classXapian_1_1Database_59e5889c489ce77fb4e7ffd80b6bc52c}{
\index{Xapian::Database@{Xapian::Database}!get_description@{get\_\-description}}
\index{get_description@{get\_\-description}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-description]{\setlength{\rightskip}{0pt plus 5cm}virtual std::string Xapian::Database::get\_\-description () const\hspace{0.3cm}{\tt  \mbox{[}virtual\mbox{]}}}}
\label{classXapian_1_1Database_59e5889c489ce77fb4e7ffd80b6bc52c}


Introspection method. 

\begin{Desc}
\item[Returns:]A string describing this object. \end{Desc}


Reimplemented in \hyperlink{classXapian_1_1WritableDatabase_714ee6f7f21fd72307329a4ba21227a0}{Xapian::Writable\-Database}.\hypertarget{classXapian_1_1Database_c13c9f754b55edf7e25d754a150bd970}{
\index{Xapian::Database@{Xapian::Database}!get_doccount@{get\_\-doccount}}
\index{get_doccount@{get\_\-doccount}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-doccount]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{types_8h_b4166dca4ac15d88c933bbb8e0d55d23}{Xapian::doccount} Xapian::Database::get\_\-doccount () const}}
\label{classXapian_1_1Database_c13c9f754b55edf7e25d754a150bd970}


Get the number of documents in the database. 

\hypertarget{classXapian_1_1Database_36b565741b2d7a5f0cfe600f811b13e7}{
\index{Xapian::Database@{Xapian::Database}!get_doclength@{get\_\-doclength}}
\index{get_doclength@{get\_\-doclength}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-doclength]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{types_8h_7272583216038f810105df7dc927723c}{Xapian::doclength} Xapian::Database::get\_\-doclength (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid} {\em did}) const}}
\label{classXapian_1_1Database_36b565741b2d7a5f0cfe600f811b13e7}


Get the length of a document. 

\hypertarget{classXapian_1_1Database_c36eafdcf748e11e533149674329f90b}{
\index{Xapian::Database@{Xapian::Database}!get_document@{get\_\-document}}
\index{get_document@{get\_\-document}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-document]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1Document}{Xapian::Document} Xapian::Database::get\_\-document (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid} {\em did}) const}}
\label{classXapian_1_1Database_c36eafdcf748e11e533149674329f90b}


Get a document from the database, given its document id. 

This method returns a \hyperlink{classXapian_1_1Document}{Xapian::Document} object which provides the information about a document.

\begin{Desc}
\item[Parameters:]
\begin{description}
\item[{\em did}]The document id for which to retrieve the data.\end{description}
\end{Desc}
\begin{Desc}
\item[Returns:]A \hyperlink{classXapian_1_1Document}{Xapian::Document} object containing the document data\end{Desc}
\begin{Desc}
\item[Exceptions:]
\begin{description}
\item[{\em Xapian::Doc\-Not\-Found\-Error}]The document specified could not be found in the database. \end{description}
\end{Desc}
\hypertarget{classXapian_1_1Database_0c180d6facca7ca0e8486e7b995a6747}{
\index{Xapian::Database@{Xapian::Database}!get_lastdocid@{get\_\-lastdocid}}
\index{get_lastdocid@{get\_\-lastdocid}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-lastdocid]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid} Xapian::Database::get\_\-lastdocid () const}}
\label{classXapian_1_1Database_0c180d6facca7ca0e8486e7b995a6747}


Get the highest document id which has been used in the database. 

\hypertarget{classXapian_1_1Database_61d9b1e634aff99280a5fcdfc5087cdc}{
\index{Xapian::Database@{Xapian::Database}!get_termfreq@{get\_\-termfreq}}
\index{get_termfreq@{get\_\-termfreq}!Xapian::Database@{Xapian::Database}}
\subsubsection[get\_\-termfreq]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{types_8h_b4166dca4ac15d88c933bbb8e0d55d23}{Xapian::doccount} Xapian::Database::get\_\-termfreq (const std::string \& {\em tname}) const}}
\label{classXapian_1_1Database_61d9b1e634aff99280a5fcdfc5087cdc}


Get the number of documents in the database indexed by a given term. 

\hypertarget{classXapian_1_1Database_759d1fde0d3d8a2ed74b83c0ebd10974}{
\index{Xapian::Database@{Xapian::Database}!keep_alive@{keep\_\-alive}}
\index{keep_alive@{keep\_\-alive}!Xapian::Database@{Xapian::Database}}
\subsubsection[keep\_\-alive]{\setlength{\rightskip}{0pt plus 5cm}void Xapian::Database::keep\_\-alive ()}}
\label{classXapian_1_1Database_759d1fde0d3d8a2ed74b83c0ebd10974}


Send a \char`\"{}keep-alive\char`\"{} to remote databases to stop them timing out. 

\hypertarget{classXapian_1_1Database_4e8badea7a9d7292c13f99429c6a2b79}{
\index{Xapian::Database@{Xapian::Database}!operator=@{operator=}}
\index{operator=@{operator=}!Xapian::Database@{Xapian::Database}}
\subsubsection[operator=]{\setlength{\rightskip}{0pt plus 5cm}void Xapian::Database::operator= (const \hyperlink{classXapian_1_1Database}{Database} \& {\em other})}}
\label{classXapian_1_1Database_4e8badea7a9d7292c13f99429c6a2b79}


Assignment is allowed. 

The internals are reference counted, so assignment is cheap. \hypertarget{classXapian_1_1Database_9fb4987b5f0e13b8344a89d1898f5500}{
\index{Xapian::Database@{Xapian::Database}!positionlist_begin@{positionlist\_\-begin}}
\index{positionlist_begin@{positionlist\_\-begin}!Xapian::Database@{Xapian::Database}}
\subsubsection[positionlist\_\-begin]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1PositionIterator}{Position\-Iterator} Xapian::Database::positionlist\_\-begin (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid} {\em did}, const std::string \& {\em tname}) const}}
\label{classXapian_1_1Database_9fb4987b5f0e13b8344a89d1898f5500}


An iterator pointing to the start of the position list for a given term in a given document. 

\hypertarget{classXapian_1_1Database_ef7093cb5cfd969c4b07593e26d208e3}{
\index{Xapian::Database@{Xapian::Database}!positionlist_end@{positionlist\_\-end}}
\index{positionlist_end@{positionlist\_\-end}!Xapian::Database@{Xapian::Database}}
\subsubsection[positionlist\_\-end]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1PositionIterator}{Position\-Iterator} Xapian::Database::positionlist\_\-end (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid}, const std::string \&) const\hspace{0.3cm}{\tt  \mbox{[}inline\mbox{]}}}}
\label{classXapian_1_1Database_ef7093cb5cfd969c4b07593e26d208e3}


Corresponding end iterator to \hyperlink{classXapian_1_1Database_9fb4987b5f0e13b8344a89d1898f5500}{positionlist\_\-begin()}. 

\hypertarget{classXapian_1_1Database_504d8e800384d12a8f9defee39362f5e}{
\index{Xapian::Database@{Xapian::Database}!postlist_begin@{postlist\_\-begin}}
\index{postlist_begin@{postlist\_\-begin}!Xapian::Database@{Xapian::Database}}
\subsubsection[postlist\_\-begin]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1PostingIterator}{Posting\-Iterator} Xapian::Database::postlist\_\-begin (const std::string \& {\em tname}) const}}
\label{classXapian_1_1Database_504d8e800384d12a8f9defee39362f5e}


An iterator pointing to the start of the postlist for a given term. 

\hypertarget{classXapian_1_1Database_c1661ac2876a4a69f327907ef47a003d}{
\index{Xapian::Database@{Xapian::Database}!postlist_end@{postlist\_\-end}}
\index{postlist_end@{postlist\_\-end}!Xapian::Database@{Xapian::Database}}
\subsubsection[postlist\_\-end]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1PostingIterator}{Posting\-Iterator} Xapian::Database::postlist\_\-end (const std::string \&) const\hspace{0.3cm}{\tt  \mbox{[}inline\mbox{]}}}}
\label{classXapian_1_1Database_c1661ac2876a4a69f327907ef47a003d}


Corresponding end iterator to \hyperlink{classXapian_1_1Database_504d8e800384d12a8f9defee39362f5e}{postlist\_\-begin()}. 

\hypertarget{classXapian_1_1Database_f140b1f8d948d13cf7be4a11a7c699a4}{
\index{Xapian::Database@{Xapian::Database}!reopen@{reopen}}
\index{reopen@{reopen}!Xapian::Database@{Xapian::Database}}
\subsubsection[reopen]{\setlength{\rightskip}{0pt plus 5cm}void Xapian::Database::reopen ()}}
\label{classXapian_1_1Database_f140b1f8d948d13cf7be4a11a7c699a4}


Re-open the database. 

This re-opens the database(s) to the latest available version(s). It can be used either to make sure the latest results are returned, or to recover from a Xapian::Database\-Modified\-Error. \hypertarget{classXapian_1_1Database_22509662f07387074beb1e9919e8e1e9}{
\index{Xapian::Database@{Xapian::Database}!term_exists@{term\_\-exists}}
\index{term_exists@{term\_\-exists}!Xapian::Database@{Xapian::Database}}
\subsubsection[term\_\-exists]{\setlength{\rightskip}{0pt plus 5cm}bool Xapian::Database::term\_\-exists (const std::string \& {\em tname}) const}}
\label{classXapian_1_1Database_22509662f07387074beb1e9919e8e1e9}


Check if a given term exists in the database. 

Return true if and only if the term exists in the database. This is the same as (get\_\-termfreq(tname) != 0), but will often be more efficient. \hypertarget{classXapian_1_1Database_c26b8f8f564c37586c7a0bd35cfefe15}{
\index{Xapian::Database@{Xapian::Database}!termlist_begin@{termlist\_\-begin}}
\index{termlist_begin@{termlist\_\-begin}!Xapian::Database@{Xapian::Database}}
\subsubsection[termlist\_\-begin]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1TermIterator}{Term\-Iterator} Xapian::Database::termlist\_\-begin (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid} {\em did}) const}}
\label{classXapian_1_1Database_c26b8f8f564c37586c7a0bd35cfefe15}


An iterator pointing to the start of the termlist for a given document. 

\hypertarget{classXapian_1_1Database_a6f20c07f93d53f35caf6c97c795a5a1}{
\index{Xapian::Database@{Xapian::Database}!termlist_end@{termlist\_\-end}}
\index{termlist_end@{termlist\_\-end}!Xapian::Database@{Xapian::Database}}
\subsubsection[termlist\_\-end]{\setlength{\rightskip}{0pt plus 5cm}\hyperlink{classXapian_1_1TermIterator}{Term\-Iterator} Xapian::Database::termlist\_\-end (\hyperlink{types_8h_53073891e45d892a8d8a5d8f87f41402}{Xapian::docid}) const\hspace{0.3cm}{\tt  \mbox{[}inline\mbox{]}}}}
\label{classXapian_1_1Database_a6f20c07f93d53f35caf6c97c795a5a1}


Corresponding end iterator to \hyperlink{classXapian_1_1Database_c26b8f8f564c37586c7a0bd35cfefe15}{termlist\_\-begin()}. 



The documentation for this class was generated from the following file:\begin{CompactItemize}
\item 
include/xapian/\hyperlink{database_8h}{database.h}\end{CompactItemize}