BDB::XML::Manager

Provides a high-level object used to manage various aspects of Berkeley DB XML usage. You use XML::Manager to perform activities such as container management (including creation and open), preparing XML::Query queries, executing one-off queries, creating transaction objects, creating update and query context objects

A XML::Manager object can be created with BDB::Env#manager

BDB::Transaction respond to the same method than BDB::XML::Manager

Class Methods

new(flags = 0)
create a new Manager object that uses a private internal database environment
flags
flags can have the value
BDB::XML::ALLOW_EXTERNAL_ACCESS
to allow queries to access external data sources
BDB::XML::ALLOW_AUTO_OPEN
to allow queries that reference unopened containers will automatically open those containers

Methods

create_container(name, flags = 0, type = XML::Container::NodeContainer, mode = 0)
Creates and opens a container. If the container already exists at the time this method is called, an exception is thrown.
name
container's name
flags
the flags to use for this container creation.
type
the type of container to create.
mode
mode for creation (see chmod(2))
create_document
create a XML::Document object
create_modify
create a XML::Modify object
create_query_context(rt = XML::Context::LiveValues, et = XML::Context::Eager)
create a XML::Context object
rt
specifies whether to return live (XML::Context::LiveValues) or dead values (XML::Context::DeadValues)
et
specifies if the resultants values are derived and stored in-memory before query evaluation is completed (XML::Context::Eager) or if they are calculated as you ask for them (XML::Query::Lazy)
create_results
create a XML::Results object
begin(flags = 0)
create a new transaction
create_update_context
create a XML::Update object
dump_container(name, path)
dump_container(name, io, to_close = false)
Dumps the contents of the specified container.
name
name of the container
path
the pathname of the file where the contents will be dumped
io
object which respond to #write
to_close
if an IO object was given, specify if this object must be closed at the end.
env
Returns the underlying environnement
home
Returns the home directory for the underlying database environment
load_container(name, path, update = nil)
load_container(name, io, to_close = false, update = nil)
Loads data from the specified path (or io) into the container.
name
name of the container to load.
path
the pathname of the file which contains the data.
io
an object which respond to #read
update
an optional update context
open_container(name, flags = 0)
Opens a container and return an XML::Container object
name
the container's name
flags
the flags to use for this container open. Specify BDB::CREATE to create and open a new container.
prepare(query, context = nil)

Compile a Query expression and return a new XML::Query object.

You can then use XML::Query#execute

query
the query to compile
context
an optional query context
query(query, context = nil) [{res| ... }

Execute a query. If a block is given it will call Xml::Results#each for the results, or it will return an Xml::Results object

This is equivalent to call XML::Manager#prepare and then XML::Query#execute

query
the query to compile
context
an optional query context
resolver = object

Register a resolver

A resolver is an object which can respond to #resolve_collection, #resolve_document, #resolve_entity, or #resolve_schema

remove_container(name)
Remove a container
name
the name of the container to be removed. The container must be closed
rename_container(old_name, new_name)
Rename a container
old_name
the name of the container to be renamed. The container must be closed and must have been opened at least once
new_name
its new name
container_flags
Return the default container flags
container_flags = flags
Set the default container flags for new XML::Container
container_type
Return the default container type
container_type = type
Set the default container type for new XML::Container
container_version(file)
Examines the named file, and if it is a container, returns a non-zero database format version. If the file does not exist, or is not a container, zero is returned.
create_index_lookup(container, uri, name, index, value = nil, op = XML::IndexLookup::EQ)
Instantiates an new XML::IndexLookup object for performing index lookup operations. Only a single index may be specified, and substring indexes are not supported.
container
The target container for the lookup operation
uri
The namespace of the node to be used. The default namespace is selected by passing an empty string for the namespace.
name
The name of the element or attribute node to be used.
index
A comma-separated list of strings that represent the indexing strategy.
value
The value to be used as the single value for an equality or inequality lookup, or as the lower bound of a range lookup.
op
Selects the operation to be performed. Must be one of: XML::IndexLookup::NONE, XML::IndexLookup::EQ, XML::IndexLookup::GT, XML::IndexLookup::GTE, XML::IndexLookup::LT, XML::IndexLookup::LTE .
pagesize
Return the current page size value
pagesize = size
Set the current page size value
reindex_container(name, context = nil, flags = 0)

Reindex an entire container. The container should be backed up prior to using this method, as it destroys existing indexes before reindexing. If the operation fails, and your container is not backed up, you may lose information.

Use this call to change the type of indexing used for a container between document-level indexes and node-level indexes. This method can take a very long time to execute, depending on the size of the container, and should not be used casually.

name
The path to the container to be reindexed.
context
The update context to use for the reindex operation.
flags
Use XML::INDEX_NODES in order to index the container at the node level; otherwise, it will be indexed at the document level.
sequence_increment = increment
Sets the integer increment to be used when pre-allocating document ids for new documents created by XML::Container::put
sequence_increment
Retrieve the integer increment.
update_container(name, context = nil)
Upgrades the container from a previous version of Berkeley DB XML
name
name of the container to be upgraded
context
an optional update context
verify_container(name, flags = 0)
verify_container(name, path, flags = BDB::SALVAGE)
verify_container(name, io, to_close = false, flags = BDB::SALVAGE)
Checks that the container data files are not corrupt, and optionally writes the salvaged container data to the specified pathname.
name
name of the container
path
name of the file where the container will be dumped if BDB::SALVAGE is set.
io
an object which respond to #write if BDB::SALVAGE is set
to_close
if true the io will be closed at end.
flags
can have the value BDB::SALVAGE, BDB::AGGRESSIVE