Microsoft Technology Licensing, LLC

Rajeev Bashyam Rajan

Balan Sethu Raman

Kangrong Yan

Jakub Kulesza

Michael James Zwilling

Peter Byrne

Steven R Schmidt

Mark Wistrom

Gregory A Smith

Shashikant Brijmohan Khandelwal

Hanumantha Rao Kodavalla

Martin J Sleeman

Artem A Oks

Vishal Kathuria

Michael J Purtell

The present invention relates to a system and method of data restoration, for instance, after the occurrence of a user error. In particular, snapshot database can be maintained that stores a copy of database data. The snapshot database does not have to store a complete copy of all data on a source database, but rather shares data that is common to both but not necessarily identical. If an error occurs on the primary database then the database can be reverted back to a point in time prior to the error by replacing source database files with snapshot files. Additionally, an undo component can be employed in conjunction with the snapshot to approach an error to a finer grained point in time. In brief, the present invention can restore a database much faster and simpler, while utilizing less space and resources than conventional data restoration technologies.

Database data recovery system and method

Methods and computer-readable media for maintaining transactional link-level consistency between a database and a file system. A file system change is logged in a record of a database log and a file corresponding to the file system change is created in a file system folder. During a restart recovery process, an analysis operation and a conditional redo operation are performed based on the database log, and a conditional redo operation and an undo operation are performed based on the files in the file system folder. An undo operation is then performed based on the database log.

Maintenance of link level consistency between database and file system

In an embodiment, a computer system instantiates an intermediary software application configured to intermediate between an event controller and a content delivery network (CDN). The event controller is configured to administer a real-time event involving multiple meeting participants. The CDN is configured to distribute dynamic, real-time content to a plurality of event participants. The intermediary software application joins the event as an event participant such that the intermediary software application receives a real-time stream of media content associated with the event from the event controller. The intermediary software application also transmits the received media content stream to computer systems of the CDN, where each CDN computer system is configured to distribute the real-time media content stream to the participants communicatively connected to the CDN.

Scalable dynamic content delivery and feedback system

Systems and methods are disclosed that facilitate providing page-level database restore functionality upon detection of a corruption event. Updates to a data page in a database can trigger generation of a snapshot of the data page, and an update log can be maintained that stores information related to page updates. Subsequent snapshots can be generated at predetermined intervals and can trigger truncation of a log segment and initiation of a new log segment. Upon detection of page corruption, a most-recent uncorrupt snapshot of the corrupt page can be identified, copied to the location of the corrupt page in the database, and modified according to the log segment associated with the uncorrupt snapshot to make the page current as of the corrupting event, all of which can be performed to restore the database without having to take the database offline.

Page recovery using volume snapshots and logs

In a database system that supports user-defined types, one or more fields of a user-defined type may be designated as containing data that is to be stored as a file outside of a database store, separate from the other fields of the type which are stored within the database. Instead of being stored within the database, the data in such a designated field of an instance of the user-defined type is stored as a file within the file system of a computer. Applications are provided 'out of band' access, via the file system of the computer, to the file in which the data of such a field is stored outside the database store. A component of the system intercepts file system open requests and checks security against the database store before allowing the open request to proceed. The component also notifies the database when file system close requests are received.

System and method for storing and retrieving a field of a user defined type outside of a database store in which the type is defined

A set of servers takes advantage of the existing data redundancy of a mirrored database to restore page corruptions. The page restore may occur with none of the time and/or administration costs of a restore from backup media and without the data loss associated with repair. Online page restore from a database mirror can be initiated and performed by the computer system automatically upon corruption detection. An entire file or database instead of an individual page or set(s) of pages can be restored. The mechanism can be used both to restore corrupt pages on the principal server from a mirror, or corrupt pages on a mirror from the principal server. Online page restore from a database mirror enables page data recovery without the need to find/load/scan through and apply data and log backups, allowing efficient and potentially automatic data recovery.

Online page restore from a database mirror

The atomicity of a transaction is extended to a filesystem as well as a database, meaning that, when the transaction is complete, all changes within the transaction to both the database and the filesystem will be either committed or not committed. Interactions may be coordinated among a client, a database resource manager, a filesystem resource manager, and a transaction manager.

System and method for database and filesystem coordinated transactions

Large, unstructured objects can be manipulated within a relational database management system (RDBMS). A 'filestream' data storage attribute is provided that can be used to tag a column in a relational table. The filestream attribute identifies the data for that column will be stored as a file in the file system in the operating system. The RDBMS manages the creation and deletion of the file in the file system. There is a 1:1 reference between the file in the file system and a cell (intersection of row and column). The data in the filestream column can be manipulated the same way as the data in other columns using a programming language, such as SQL or MICROSOFT&#xae;'s T-SQL.

Filestream data storage attribute

A type of an object that can be persisted in a database store is defined by a user. The type definition comprises fields and behaviors, each field having a respective data type. One or more fields of the type definition may be designated as containing data of a type that is to be stored as a file outside of the database store and separately from the other fields of the type definition. When a request is received to store an object that is an instance of the user defined type, the data in any so designated field of the object is stored in a file outside of the database store, preferably within a file system of the computer on which the database store is implemented. The data in each of the other fields of the object is stored within the database store in the usual manner. The database store maintains a link, or reference, between the persisted object and the data of the field that is stored as a file outside of the database store. Applications are provided 'out of band' access, via the file system of the computer, to the file in which the data of given field is stored outside the database store.

Growing community of inventors

Kirkland, WA, United States of America

Rajeev Bashyam Rajan