NAME¶
Search::Xapian::WritableDatabase - writable database object
DESCRIPTION¶
This class represents a Xapian database for indexing. It's a subclass of
Search::Xapian::Database, which is used for searching.
METHODS¶
- new <database> or new <path> <mode>
- Class constructor. Takes either a database object, or a
path and one of DB_OPEN, DB_CREATE, DB_CREATE_OR_OPEN or
DB_CREATE_OR_OVERWRITE. These are exported by Search::Xapian with the 'db'
option.
- clone
- Return a clone of this class.
- flush
- Flush to disk any modifications made to the database.
For efficiency reasons, when performing multiple updates to a database it is
best (indeed, almost essential) to make as many modifications as memory
will permit in a single pass through the database. To ensure this, Xapian
batches up modifications.
Flush may be called at any time to ensure that the modifications which have
been made are written to disk: if the flush succeeds, all the preceding
modifications will have been written to disk.
If any of the modifications fail, an exception will be thrown and the
database will be left in a state in which each separate addition,
replacement or deletion operation has either been fully performed or not
performed at all: it is then up to the application to work out which
operations need to be repeated.
Beware of calling flush too frequently: this will have a severe performance
cost.
Note that flush need not be called explicitly: it will be called
automatically when the database is closed, or when a sufficient number of
modifications have been made.
- add_document <document>
- Add a new document to the database.
This method adds the specified document to the database, returning a newly
allocated document ID.
Note that this does not mean the document will immediately appear in the
database; see flush() for more details.
As with all database modification operations, the effect is atomic: the
document will either be fully added, or the document fails to be added and
an exception is thrown (possibly at a later time when flush is called or
the database is closed).
- delete_document <doc_id>
- Delete a document from the database. This method removes
the document with the specified document ID from the database.
Note that this does not mean the document will immediately disappear from
the database; see flush() for more details.
As with all database modification operations, the effect is atomic: the
document will either be fully removed, or the document fails to be removed
and an exception is thrown (possibly at a later time when flush is called
or the database is closed).
- delete_document_by_term <term>
- Delete any documents indexed by a term from the database.
This method removes any documents indexed by the specified term from the
database.
The intended use is to allow UIDs from another system to easily be mapped to
terms in Xapian, although this method probably has other uses.
- replace_document <doc_id> <document>
- eplace a given document in the database.
This method replaces the document with the specified document ID. Note that
this does not mean the document will immediately change in the database;
see flush() for more details.
As with all database modification operations, the effect is atomic: the
document will either be fully replaced, or the document fails to be
replaced and an exception is thrown (possibly at a later time when flush
is called or the database is closed).
- replace_document_by_term <unique_term>
<document>
- Replace any documents matching an unique term.
This method replaces any documents indexed by the specified term with the
specified document. If any documents are indexed by the term, the lowest
document ID will be used for the document, otherwise a new document ID
will be generated as for add_document.
The intended use is to allow UIDs from another system to easily be mapped to
terms in Xapian, although this method probably has other uses.
Note that this does not mean the document(s) will immediately change in the
database; see flush() for more details.
As with all database modification operations, the effect is atomic: the
document(s) will either be fully replaced, or the document(s) fail to be
replaced and an exception is thrown (possibly at a later time when flush
is called or the database is closed).
- add_spelling <word> <freqinc>
- Add a word to the spelling dictionary.
If the word is already present, its frequency is increased.
Parameters:
word The word to add.
freqinc How much to increase its frequency by (default 1).
- remove_spelling <word> <freqdec>
- Remove a word from the spelling dictionary.
The word's frequency is decreased, and if would become zero or less then the
word is removed completely.
Parameters:
word The word to remove.
freqdec How much to decrease its frequency by (default 1).
- reopen
- Re-open the database to ensure you are using the latest
revision.
- close
- Close the database. This also implies a commit()
unless a transaction is in progress.
SEE ALSO¶
Search::Xapian,Search::Xapian::Enquire,Search::Xapian::Database