#include <DbXml.hpp> XmlResults results = XmlIndexLookup::execute( XmlQueryContext &context, u_int32_t flags = 0) const XmlResults results = XmlIndexLookup::execute( XmlTransaction &txn, XmlQueryContext &context, u_int32_t flags = 0) const
Executes the index lookup operation specified by the configuration of the XmlIndexLookup object.
If the operation is to be transaction-protected, the
txn
parameter is an
XmlTransaction
handle
returned from XmlManager::createTransaction.
The XmlQueryContext to use for this query.
This parameter must be set to 0 or by bitwise inclusively OR'ing together one or more of the following values:
DBXML_LAZY_DOCS
Retrieve the document lazily. That is, retrieve document content and document metadata only on an as needed basis when reading the document.
DBXML_WELL_FORMED_ONLY
Force the use of a scanner that will neither validate nor read schema or dtds associated with the document during parsing. This is efficient, but can cause parsing errors if the document references information that might have come from a schema or dtd, such as entity references.
DB_READ_UNCOMMITTED
This operation will support degree 1 isolation; that is,
read operations may return data that has been modified
by other transactions but which has not yet been
committed. Silently ignored if the DB_READ_UNCOMMITTED
flag was not specified when the underlying container was
opened.
DB_READ_COMMITTED
This operation will have degree 2 isolation. This provides for cursor stability but not repeatable reads. Data items which have been previously read by this transaction may be deleted or modified by other transactions before this transaction completes.
DB_RMW
Acquire write locks instead of read locks when doing the read, if locking is configured. Setting this flag can eliminate deadlock during a read-modify-write cycle by acquiring the write lock during the read part of the cycle so that another thread of control acquiring a read lock for the same item, in its own read-modify-write cycle, will not result in deadlock.
DBXML_REVERSE_ORDER
Return results in reverse order relative to the sort of the index.
DBXML_NO_INDEX_NODES
Relevant for node storage containers with node indices
only. Causes the
XmlIndexLookup::execute()
operations to return document nodes rather than direct
pointers to the interior nodes. This is more efficient
if all that is desired is a reference to target
documents.
DBXML_CACHE_DOCUMENTS
Enables use of a cache mechanism that optimizes
XmlIndexLookup::execute()
operations that a large number of nodes from the same document.