Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising monitoring access to a plurality of rows in a database partition, a first portion of the plurality of rows stored in a persistent page store and a second portion of the plurality of rows stored in an in-memory row store. The operations can further comprise determining workload parameters based on the monitoring, selecting a location for performing a database operation on the database partition based on the workload parameters, and performing the database operation on the database partition within the selected location (e.g., the persistent page store or the in-memory row store). Related systems, methods, and articles of manufacture are also described.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: Example methods and systems are directed to existence checks on rows within a database. A page data structure stores bitmap data for the rows in the page. A row within the page corresponds to a single bit in the bitmap data. To determine if a row has been deleted, the page data structure for the page containing the row is located and the bit for the row in the page data structure is checked. An array of page data structures is created, indexed by a hash of the page identifier. In the event of a hash collision, a linked list of page data structures is used, sorted by page identifier.

Abstract: Example methods and systems are directed to existence checks on rows within a database. A page data structure stores bitmap data for the rows in the page. A row within the page corresponds to a single bit in the bitmap data. To determine if a row has been deleted, the page data structure for the page containing the row is located and the bit for the row in the page data structure is checked. An array of page data structures is created, indexed by a hash of the page identifier. In the event of a hash collision, a linked list of page data structures is used, sorted by page identifier.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising adding a data row to an in-memory row store at a row location based on a database operation, indexing the row location in an index table comprising a plurality of nodes for a plurality of rows in the in-memory row store, the plurality of nodes organized across a plurality of buckets, and accessing the data row at the row location in the in-memory row store based on the index table to perform another database operation on the data row Related systems, methods, and articles of manufacture are also described.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising processing a database transaction affecting at least a first row in an in-memory row store and at least a second row in a persistent page store, logging changes to the second row within a page store transaction log as part of the processing and prior to committing the database transaction, logging a final aggregated result of the first row as part of committing the database transaction within a row store transaction log that is separate and distinct from the page store transaction log, and altering at least a portion of the in-memory row store based on accessing the row store transaction log. Related systems, methods, and articles of manufacture are also described.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: Example methods and systems are directed to existence checks on rows within a database. A page data structure stores bitmap data for the rows in the page. A row within the page corresponds to a single bit in the bitmap data. To determine if a row has been deleted, the page data structure for the page containing the row is located and the bit for the row in the page data structure is checked. An array of page data structures is created, indexed by a hash of the page identifier. In the event of a hash collision, a linked list of page data structures is used, sorted by page identifier.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising determining that data stored at a first location in a persistent page store is active, copying the data to a second location in an in-memory row store in response to determining that the data is active, indexing the data in an index table in response to determining that the data is active, accessing the data at the second location in the in-memory row store based on the index table, and performing an update of the data in the in-memory row store. Related systems, methods, and articles of manufacture are also described.

Abstract: Data recovery in a database includes performing a backward scan of a transaction log that records transactions made on the database. The backward scan includes traversing log records starting from a latest-in-time log record toward the beginning of the transaction log. Each log record can be replayed to recover data for a database row associated with the log record. An earlier-in-time log record is skipped if the associate database row has been recovered by later-in-time log record.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising monitoring access to a plurality of rows in a database partition, a first portion of the plurality of rows stored in a persistent page store and a second portion of the plurality of rows stored in an in-memory row store. The operations can further comprise determining workload parameters based on the monitoring, selecting a location for performing a database operation on the database partition based on the workload parameters, and performing the database operation on the database partition within the selected location (e.g., the persistent page store or the in-memory row store). Related systems, methods, and articles of manufacture are also described.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising adding a data row to an in-memory row store at a row location based on a database operation, indexing the row location in an index table comprising a plurality of nodes for a plurality of rows in the in-memory row store, the plurality of nodes organized across a plurality of buckets, and accessing the data row at the row location in the in-memory row store based on the index table to perform another database operation on the data row Related systems, methods, and articles of manufacture are also described.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising determining that data stored at a first location in a persistent page store is active, copying the data to a second location in an in-memory row store in response to determining that the data is active, indexing the data in an index table in response to determining that the data is active, accessing the data at the second location in the in-memory row store based on the index table, and performing an update of the data in the in-memory row store. Related systems, methods, and articles of manufacture are also described.

Abstract: A system for an in-memory row storage architecture can be provided. In some implementations, the system performs operations comprising processing a database transaction affecting at least a first row in an in-memory row store and at least a second row in a persistent page store, logging changes to the second row within a page store transaction log as part of the processing and prior to committing the database transaction, logging a final aggregated result of the first row as part of committing the database transaction within a row store transaction log that is separate and distinct from the page store transaction log, and altering at least a portion of the in-memory row store based on accessing the row store transaction log. Related systems, methods, and articles of manufacture are also described.