Abstract: A technique for migrating (e.g., “copying” or “moving”) temporary data from one session to another session is provided. While executing a workload associated with a particular session, session state is created. A subset of the session state comprises large objects that are referred to as “temporary data.” Thus, temporary data is stored in a database (instead of in the database server) and is normally deleted when the particular session is deleted. To avoid this deletion when the session state is migrated to a different session, the temporary data, in one embodiment, is saved in an external storage that is separate from the database. An external table is created in the external storage and stores the temporary data. Location information to access the external table is provided to the other session.

Abstract: User-level bookmarks are initially created at a specified offset in a large object (LOB) of a database and automatically updated to reflect a new offset, if necessary, after database updates. By logically linking the bookmark to a data element, the bookmark continues to point to the same logical data element as it did before the update. An API provides the functionality of immutable bookmarks by automatically changing the offset of the bookmark following sliding inserts or deletions of data to the database.

Abstract: Systems, methods, and other embodiments associated with selectively acquiring and utilizing query statistics are described. One example method includes selectively acquiring statistics associated with search queries submitted to a search process during a sample period. The statistics may be associated with an index and tokens associated with the index and search queries. The method may also include selecting tokens and/or queries to optimize based, at least in part, on the statistics. In one example, whether and/or how the tokens and/or queries are optimized may depend on estimating index fragmentation based, at least in part, on the statistics.

Abstract: Techniques for partitioning nested tables are provided. A parent table includes a column for collection items. A nested table is created for storing items that belong to the collection items. The nested table is partitioned to create a plurality of nested table partitions. Each nested table partition is a distinct, separately stored structure within a database. How the nested table is partitioned may, or may not, be based on how the parent table is partitioned. For example, a nested table may be partitioned based on the same criteria in which the parent table is partitioned. As another example, a nested table may be partitioned, whereas the parent table is not partitioned.

Abstract: A technique for migrating (e.g., “copying” or “moving”) temporary data from one session to another session is provided. While executing a workload associated with a particular session, session state is created. A subset of the session state comprises large objects that are referred to as “temporary data.” Thus, temporary data is stored in a database (instead of in the database server) and is normally deleted when the particular session is deleted. To avoid this deletion when the session state is migrated to a different session, the temporary data, in one embodiment, is saved in an external storage that is separate from the database. An external table is created in the external storage and stores the temporary data. Location information to access the external table is provided to the other session.

Abstract: Instances of complex types are logically replicated. In general, the logical replication of complex types involves converting a complex type instance from its storage format into a logical representation written in a markup language, like XML. The logical representation is then propagated to a destination (or destinations), which converts the logical representation to a storage format used at the destination for that complex type.

Abstract: User-level bookmarks are initially created at a specified offset in a large object (LOB) of a database and automatically updated to reflect a new offset, if necessary, after database updates. By logically linking the bookmark to a data element, the bookmark continues to point to the same logical data element as it did before the update. An API provides the functionality of immutable bookmarks by automatically changing the offset of the bookmark following sliding inserts or deletions of data to the database.

Abstract: Techniques are described herein for altering the datatype of a column without having to immediately migrate the data items that currently reside in the column. In one embodiment, the alteration is performed without migration by creating a new column having the desired datatype while retaining the old column. Instead of migrating the data items from to the new column at the time the column is altered, the items remain in the original column until the items are updated.

Abstract: Efficiently replicating XML data among databases includes techniques for (a) replicating XML data involved with an insert operation; (b) replicating XML data involved with an update operation; (c) leveraging existing relational replication techniques for XML data stored in shredded form using object-relational constructs; and (d) replicating XQuery Data Model sequences. Each technique reduces the amount of information that would otherwise need to be transmitted over a network for XML data replication purposes.

Abstract: A method and apparatus for receiving objects is provided. Embodiments provide for receiving, from a source database server, at a target database server, an object. If the object type of the object is involved in an inheritance hierarchy, then the target database server inspects the object to determine a source identifier that identifies to a source database server the object type associated with the object. The target database determines a target identifier that identifies to the target database server the object type associated with the object based on a mapping that associates source identifiers to target identifiers. Alternately, if the object type of the object is not involved in an inheritance hierarchy, then the target database server inspects the object to determine a set of characteristics of the object. The target database server determines the target identifier for the object based on the characteristics of the object.