Xapian::WritableDatabase - writable database object

- NAME
- DESCRIPTION
- METHODS
- SEE ALSO

# NAME

Xapian::WritableDatabase - writable database object

# DESCRIPTION

This class represents a Xapian database for indexing. It's a subclass of 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 Xapian with the 'db' option.

clone

  Return a clone of this class.

commit

  Commit 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.

  Commit may be called at any time to ensure that the modifications which have been made are written to disk: if the commit 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 commit too frequently: this will have a severe performance cost.

  Note that commit 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 commit() 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 commit 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 commit() 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 commit 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 commit() 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 commit 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 commit() 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 commit 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

Xapian, Xapian::Enquire, Xapian::Database