Abstract: High availability and disaster recovery can be achieved within a database management system by detecting which parts of a file have changed and sending the changed parts to secondary servers, without sending the entire file that has experienced the changes. A log cracker reads data from a transaction log that stores records from a database and a separately maintained file system. The log cracker sends mirror commands with some of the transaction log data to the file system to initiate mirroring of the data from the file system to secondary servers. The log data is then subsequently sent to the secondary servers as well, to enable identification of changed data without having to transfer the entire file that has been changed.

Abstract: A method for mirroring one or more data changes from a first database server to one or more second database servers. The method includes intercepting one or more operations that make one or more changes to one or more data on the first database server. After intercepting these operations, the method merges the operations into one or more chunks, adds one or more log records having the chunks into a database log. The database log includes one or more database log blocks. The method then writes the database log blocks.

Abstract: An item providing system may receive digital content that is to be provided to user devices. The digital content may include electronic periodicals (e.g., electronic newspapers, electronic magazines, etc.). The digital content may not be complete. To address this issue, the item providing system may include a content reconstruction tool that is able to identify and download needed portions of digital content. Also, the digital content may not be in a desired format. The item providing system may include a collator tool that is able to organize, arrange and/or format the digital content.

Abstract: The present invention extends to methods, systems, and computer program products for mirroring file data. Generally, high availability and disaster recovery (“HADRON”) is achieved within a database management system by detecting which parts of a file have changed and sending the changed parts to secondaries. Adjacent or partially overlapping parts of a file can coalesce to form larger chunks of changed data. Coalescing reduces the overall number of chunks that are tracked.

Abstract: A method for mirroring one or more data changes from a first database server to one or more second database servers. The method includes intercepting one or more operations that make one or more changes to one or more data on the first database server. After intercepting these operations, the method merges the operations into one or more chunks, adds one or more log records having the chunks into a database log. The database log includes one or more database log blocks. The method then writes the database log blocks.