InMemoryDatabase Class Reference

A database held entirely in memory. More...

#include <inmemory_database.h>

Inheritance diagram for InMemoryDatabase:

[legend]Collaboration diagram for InMemoryDatabase:


Public Member Functions
	InMemoryDatabase ()
	Create and open an in-memory database.
	~InMemoryDatabase ()
Xapian::doccount	get_doccount () const
	Return the number of docs in this (sub) database.
Xapian::docid	get_lastdocid () const
	Return the last used document id of this (sub) database.
Xapian::doclength	get_avlength () const
	Return the average length of a document in this (sub) database.
Xapian::doclength	get_doclength (Xapian::docid did) const
	Get the length of a given document.
Xapian::doccount	get_termfreq (const string &tname) const
	Return the number of documents indexed by a given term.
Xapian::termcount	get_collection_freq (const string &tname) const
	Return the total number of occurrences of the given term.
bool	term_exists (const string &tname) const
	Check whether a given term is in the database.
bool	has_positions () const
	Check whether this database contains any positional information.
LeafPostList *	open_post_list (const string &tname) const
	Open a posting list.
TermList *	open_term_list (Xapian::docid did) const
	Open a term list.
Xapian::Document::Internal *	open_document (Xapian::docid did, bool lazy=false) const
	Open a document.
std::string	get_metadata (const std::string &key) const
void	set_metadata (const std::string &key, const std::string &value)
Xapian::termcount	positionlist_count (Xapian::docid did, const string &tname) const
PositionList *	open_position_list (Xapian::docid did, const string &tname) const
	Open a position list for the given term in the given document.
TermList *	open_allterms (const string &prefix) const
	Open an allterms list.
Private Member Functions
InMemoryDatabase &	operator= (const InMemoryDatabase &)
	InMemoryDatabase (const InMemoryDatabase &)
void	make_term (const string &tname)
bool	doc_exists (Xapian::docid did) const
Xapian::docid	make_doc (const string &docdata)
void	finish_add_doc (Xapian::docid did, const Xapian::Document &document)
void	add_values (Xapian::docid did, const map< Xapian::valueno, string > &values_)
void	make_posting (InMemoryDoc *doc, const string &tname, Xapian::docid did, Xapian::termpos position, Xapian::termcount wdf, bool use_position=true)

void	flush ()
	Implementation of virtual methods: see Database for details.
void	cancel ()
	Cancel pending modifications to the database.
Xapian::docid	add_document (const Xapian::Document &document)
	Add a new document to the database.
void	delete_document (Xapian::docid did)
	Delete a document in the database.
void	replace_document (Xapian::docid did, const Xapian::Document &document)
	Replace a given document in the database.
Private Attributes
map< string, InMemoryTerm >	postlists
vector< InMemoryDoc >	termlists
vector< std::string >	doclists
vector< std::map< Xapian::valueno, string > >	valuelists
vector< Xapian::doclength >	doclengths
std::map< string, string >	metadata
Xapian::doccount	totdocs
Xapian::doclength	totlen
bool	positions_present
Friends
class	InMemoryAllDocsPostList

Detailed Description

A database held entirely in memory.

This is a prototype database, mainly used for debugging and testing.

Definition at line 231 of file inmemory_database.h.

Constructor & Destructor Documentation

InMemoryDatabase::InMemoryDatabase ( const InMemoryDatabase & ) [private]

InMemoryDatabase::InMemoryDatabase ( )

Create and open an in-memory database.

Exceptions:

Xapian::DatabaseOpeningError

thrown if database can't be opened.

Definition at line 352 of file inmemory_database.cc.

References Xapian::Database::Internal::transaction_state, and Xapian::Database::Internal::TRANSACTION_UNIMPLEMENTED.

InMemoryDatabase::~InMemoryDatabase ( )

Definition at line 359 of file inmemory_database.cc.

References Xapian::Database::Internal::dtor_called().

Member Function Documentation

InMemoryDatabase& InMemoryDatabase::operator= ( const InMemoryDatabase & ) [private]

void InMemoryDatabase::make_term ( const string & tname ) [private]

Definition at line 683 of file inmemory_database.cc.

References postlists.

Referenced by finish_add_doc().

bool InMemoryDatabase::doc_exists ( Xapian::docid did ) const [private]

Definition at line 384 of file inmemory_database.cc.

References termlists.

Referenced by delete_document(), get_doclength(), make_posting(), open_document(), open_position_list(), open_term_list(), positionlist_count(), and replace_document().

Xapian::docid InMemoryDatabase::make_doc ( const string & docdata ) [private]

Definition at line 689 of file inmemory_database.cc.

References AssertEqParanoid, doclengths, doclists, and termlists.

Referenced by add_document().

void InMemoryDatabase::finish_add_doc	(	Xapian::docid	did,
		const Xapian::Document &	document
	)			`[private]`

void InMemoryDatabase::add_values	(	Xapian::docid	did,
		const map< Xapian::valueno, string > &	values_
	)			`[private]`

Definition at line 519 of file inmemory_database.cc.

References valuelists.

Referenced by finish_add_doc().

void InMemoryDatabase::make_posting	(	InMemoryDoc *	doc,
		const string &	tname,
		Xapian::docid	did,
		Xapian::termpos	position,
		Xapian::termcount	wdf,
		bool	use_position = `true`
	)			`[private]`

Definition at line 700 of file inmemory_database.cc.

References InMemoryDoc::add_posting(), Assert, InMemoryPosting::did, doc_exists(), doclengths, InMemoryTermEntry::positions, InMemoryPosting::positions, postlists, termlists, InMemoryTermEntry::tname, InMemoryPosting::valid, InMemoryTermEntry::wdf, and InMemoryPosting::wdf.

Referenced by finish_add_doc().

void InMemoryDatabase::flush ( ) [private, virtual]

Implementation of virtual methods: see Database for details.

Reimplemented from Xapian::Database::Internal.

Definition at line 530 of file inmemory_database.cc.

void InMemoryDatabase::cancel ( ) [private, virtual]

Cancel pending modifications to the database.

Reimplemented from Xapian::Database::Internal.

Definition at line 536 of file inmemory_database.cc.

Xapian::docid InMemoryDatabase::add_document ( const Xapian::Document & document ) [private, virtual]

Add a new document to the database.

See WritableDatabase::add_document() for more information.

Reimplemented from Xapian::Database::Internal.

Definition at line 624 of file inmemory_database.cc.

References DEBUGLINE, finish_add_doc(), Xapian::Document::get_data(), and make_doc().

void InMemoryDatabase::delete_document ( Xapian::docid did ) [private, virtual]

Delete a document in the database.

See WritableDatabase::delete_document() for more information.

Reimplemented from Xapian::Database::Internal.

Definition at line 541 of file inmemory_database.cc.

References Assert, doc_exists(), doclengths, doclists, om_tostring(), positions_present, postlists, termlists, totdocs, totlen, and valuelists.

void InMemoryDatabase::replace_document	(	Xapian::docid	did,
		const Xapian::Document &	document
	)			`[private, virtual]`

Replace a given document in the database.

See WritableDatabase::replace_document() for more information.

Reimplemented from Xapian::Database::Internal.

Definition at line 578 of file inmemory_database.cc.

References Assert, DEBUGLINE, doc_exists(), doclengths, doclists, finish_add_doc(), Xapian::Document::get_data(), postlists, termlists, totdocs, totlen, and valuelists.

Xapian::doccount InMemoryDatabase::get_doccount ( ) const [virtual]

Return the number of docs in this (sub) database.

Implements Xapian::Database::Internal.

Definition at line 406 of file inmemory_database.cc.

References totdocs.

Xapian::docid InMemoryDatabase::get_lastdocid ( ) const [virtual]

Return the last used document id of this (sub) database.

Implements Xapian::Database::Internal.

Definition at line 412 of file inmemory_database.cc.

References termlists.

Xapian::doclength InMemoryDatabase::get_avlength ( ) const [virtual]

Return the average length of a document in this (sub) database.

See Database::Internal::get_doclength() for the meaning of document length within Xapian.

Implements Xapian::Database::Internal.

Definition at line 418 of file inmemory_database.cc.

References totdocs, and totlen.

Xapian::doclength InMemoryDatabase::get_doclength ( Xapian::docid did ) const [virtual]

Get the length of a given document.

Document length, for the purposes of Xapian, is defined to be the number of instances of terms within a document. Expressed differently, the sum of the within document frequencies over all the terms in the document.

Parameters:

did

The document id of the document whose length is being requested.

Implements Xapian::Database::Internal.

Definition at line 425 of file inmemory_database.cc.

References doc_exists(), doclengths, and om_tostring().

Referenced by open_term_list().

Xapian::doccount InMemoryDatabase::get_termfreq ( const string & tname ) const [virtual]

Return the number of documents indexed by a given term.

This may be an approximation, but must be an upper bound (ie, greater or equal to the true value), and should be as accurate as possible.

Parameters:

tname

The term whose term frequency is being requested.

Implements Xapian::Database::Internal.

Definition at line 390 of file inmemory_database.cc.

References postlists.

Xapian::termcount InMemoryDatabase::get_collection_freq ( const string & tname ) const [virtual]

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: ie, the sum of the within document frequencies of the term.

Parameters:

tname

The term whose collection frequency is being requested.

Implements Xapian::Database::Internal.

Definition at line 398 of file inmemory_database.cc.

References postlists.

bool InMemoryDatabase::term_exists ( const string & tname ) const [virtual]

Check whether a given term is in the database.

Parameters:

tname

The term whose presence is being checked.

Implements Xapian::Database::Internal.

Definition at line 738 of file inmemory_database.cc.

References Assert, and postlists.

bool InMemoryDatabase::has_positions ( ) const [virtual]

Check whether this database contains any positional information.

Implements Xapian::Database::Internal.

Definition at line 747 of file inmemory_database.cc.

References positions_present.

LeafPostList * InMemoryDatabase::open_post_list ( const string & tname ) const [virtual]

Open a posting list.

Method defined by subclass to open a posting list. This is a list of all the documents which contain a given term.

Parameters:

tname

The term whose posting list is being requested.

Returns:: A pointer to the newly created posting list. If the term doesn't exist, a new EmptyPostList object (or an object which behaves the same way) is returned instead, which makes it easier to implement a search over multiple databases. This object must be deleted by the caller after use.

Implements Xapian::Database::Internal.

Definition at line 365 of file inmemory_database.cc.

References Assert, Xapian::PostingIterator::Internal::at_end(), InMemoryAllDocsPostList, postlists, and termlists.

TermList * InMemoryDatabase::open_term_list ( Xapian::docid did ) const [virtual]

Open a term list.

This is a list of all the terms contained by a given document.

Parameters:

did

The document id whose term list is being requested.

Returns:: A pointer to the newly created term list. This object must be deleted by the caller after use.

Implements Xapian::Database::Internal.

Definition at line 435 of file inmemory_database.cc.

References doc_exists(), get_doclength(), om_tostring(), and termlists.

Xapian::Document::Internal * InMemoryDatabase::open_document	(	Xapian::docid	did,
		bool	lazy = `false`
	)			const `[virtual]`

Open a document.

This is used to access the values and data associated with a document. See class Xapian::Document::Internal for further details.

Parameters:

	did	The document id which is being requested.
	lazy	Don't check the document exists immediately - use from within the matcher where we know the document exists, and don't want to read the record when we just want the values.