Abstract: Various technologies described herein pertain to accessing records of an in-memory database. A memory can include a primary storage and a data store can include a secondary storage. The primary storage includes a first subset of the records of the database, and the secondary storage includes a second subset of the records of the database. Moreover, the memory includes an update memo that includes timestamp notices. The timestamp notices specify statuses of records of the database having updates that span the primary storage and the secondary storage. The memory further includes a database management system that is executable by a processor. The database management system processes a transaction. Further, the database management system includes a storage interface component that accesses a record of the database for the transaction based on at least one of the timestamp notices of the update memo.

Abstract: Various technologies described herein pertain to accessing records of an in-memory database. A memory can include a primary storage and a data store can include a secondary storage. The primary storage includes a first subset of the records of the database, and the secondary storage includes a second subset of the records of the database. Moreover, the memory includes an update memo that includes timestamp notices. The timestamp notices specify statuses of records of the database having updates that span the primary storage and the secondary storage. The memory further includes a database management system that is executable by a processor. The database management system processes a transaction. Further, the database management system includes a storage interface component that accesses a record of the database for the transaction based on at least one of the timestamp notices of the update memo.

Abstract: Various technologies described herein pertain to accessing records of an in-memory database. A memory can include a primary storage and a data store can include a secondary storage. The primary storage includes a first subset of the records of the database, and the secondary storage includes a second subset of the records of the database. Moreover, the memory includes an update memo that includes timestamp notices. The timestamp notices specify statuses of records of the database having updates that span the primary storage and the secondary storage. The memory further includes a database management system that is executable by a processor. The database management system processes a transaction. Further, the database management system includes a storage interface component that accesses a record of the database for the transaction based on at least one of the timestamp notices of the update memo.

Abstract: A transaction engine includes a multi-version concurrency control (MVCC) module that accesses a latch-free hash table that includes respective hash table entries that include respective buckets of respective bucket items. The bucket items represent respective records, the respective bucket items each including a value indicating a temporal most recent read time of the item and a version list of descriptions that describe respective versions of the respective records, the MVCC module performing timestamp order concurrency control, using the latch-free hash table. Recovery log buffers may be used as cache storage for the transaction engine.

Abstract: Various technologies described herein pertain to classifying data in a main memory database system. A record access log can include a sequence of record access observations logged over a time period from a beginning time to an end time. Each of the record access observations can include a respective record ID and read timestamp. The record access log can be scanned in reverse from the end time towards the beginning time. Further, access frequency estimate data for records corresponding to record IDs read from the record access log can be calculated. The access frequency estimate data can include respective upper bounds and respective lower bounds of access frequency estimates for each of the records. Moreover, the records can be classified based on the respective upper bounds and the respective lower bounds of the access frequency estimates, such that K records can be classified as being frequently accessed records.

Abstract: Various technologies described herein pertain to classifying data in a main memory database system. A record access log can include a sequence of record access observations logged over a time period from a beginning time to an end time. Each of the record access observations can include a respective record ID and read timestamp. The record access log can be scanned in reverse from the end time towards the beginning time. Further, access frequency estimate data for records corresponding to record IDs read from the record access log can be calculated. The access frequency estimate data can include respective upper bounds and respective lower bounds of access frequency estimates for each of the records. Moreover, the records can be classified based on the respective upper bounds and the respective lower bounds of the access frequency estimates, such that K records can be classified as being frequently accessed records.

Abstract: Various technologies described herein pertain to classifying data in a main memory database system. A record access log can include a sequence of record access observations logged over a time period from a beginning time to an end time. Each of the record access observations can include a respective record ID and read timestamp. The record access log can be scanned in reverse from the end time towards the beginning time. Further, access frequency estimate data for records corresponding to record IDs read from the record access log can be calculated. The access frequency estimate data can include respective upper bounds and respective lower bounds of access frequency estimates for each of the records. Moreover, the records can be classified based on the respective upper bounds and the respective lower bounds of the access frequency estimates, such that K records can be classified as being frequently accessed records.

Abstract: Update requests that specify updates to a logical page associated with a key-value store are obtained. Updates to the logical page are posted using the obtained plurality of update requests, without accessing the logical page via a read operation.

Abstract: A transaction engine includes a multi-version concurrency control (MVCC) module that accesses a latch-free hash table that includes respective hash table entries that include respective buckets of respective bucket items. The bucket items represent respective records, the respective bucket items each including a value indicating a temporal most recent read time of the item and a version list of descriptions that describe respective versions of the respective records, the MVCC module performing timestamp order concurrency control, using the latch-free hash table. Recovery log buffers may be used as cache storage for the transaction engine.

Abstract: Update requests that specify updates to a logical page associated with a key-value store are obtained. Updates to the logical page are posted using the obtained plurality of update requests, without accessing the logical page via a read operation.

Abstract: Various technologies described herein pertain to accessing records of an in-memory database. A memory can include a primary storage and a data store can include a secondary storage. The primary storage includes a first subset of the records of the database, and the secondary storage includes a second subset of the records of the database. Moreover, the memory includes an update memo that includes timestamp notices. The timestamp notices specify statuses of records of the database having updates that span the primary storage and the secondary storage. The memory further includes a database management system that is executable by a processor. The database management system processes a transaction. Further, the database management system includes a storage interface component that accesses a record of the database for the transaction based on at least one of the timestamp notices of the update memo.

Abstract: Various technologies described herein pertain to classifying data in a main memory database system. A record access log can include a sequence of record access observations logged over a time period from a beginning time to an end time. Each of the record access observations can include a respective record ID and read timestamp. The record access log can be scanned in reverse from the end time towards the beginning time. Further, access frequency estimate data for records corresponding to record IDs read from the record access log can be calculated. The access frequency estimate data can include respective upper bounds and respective lower bounds of access frequency estimates for each of the records. Moreover, the records can be classified based on the respective upper bounds and the respective lower bounds of the access frequency estimates, such that K records can be classified as being frequently accessed records.