Abstract: A hybrid transactional/analytical processing (HTAP) database includes an online transaction processing (OLTP) engine, an online analytical processing (OLAP) engine provided separately from the OLTP engine, and a shared storage holding data of multiple tenants. The shared storage is configured to receive a request for a first scan from a first tenant and a request for a second scan from a second tenant, execute the first scan, and after a predetermined first period of time has elapsed without the first scan finishing, pause the first scan and execute the second scan.

Abstract: Described are examples for decoding variable length integers including obtaining a series of bits encoding one or more variable length integers, applying a mask to the series of bits to determine a number of bytes that correspond to each of the one or more variable length integers in the series of bits, and decoding each of the one or more variable length integers based on the number of bytes that correspond to each of the one or more variable length integers.

Abstract: A method for data redistribution of a job data in a first datanode (DN) to at least one additional DN in a Massively Parallel Processing (MPP) Database (DB) is provided. The method includes recording a snapshot of the job data, creating a first data portion in the first DN and a redistribution data portion in the first DN, collecting changes to a job data copy stored in a temporary table, and initiating transfer of the redistribution data portion to the at least one additional DN.

Abstract: Transaction processing for a database distributed across availability zones is disclosed, including: determining that a transaction comprising a set of one or more statements is to be executed on a plurality of database servers across at least two availability zones, wherein each availability zone is associated with a respective hybrid logical clock (HLC)-based centralized time service; causing the set of one or more statements to execute on the plurality of database servers across the at least two availability zones; obtaining a plurality of HLC-based prepare timestamps from the plurality of database servers across the at least two availability zones; selecting a maximum HLC-based prepare timestamp to use as a commit timestamp associated with the transaction; and determining whether to return a commit result corresponding to the transaction after a time delay that is determined based at least in part on a predetermined time skew.

Abstract: A method for data redistribution of a job data in a first datanode (DN) to at least one additional DN in a Massively Parallel Processing (MPP) Database (DB) is provided. The method includes recording a snapshot of the job data, creating a first data portion in the first DN and a redistribution data portion in the first DN, collecting changes to a job data copy stored in a temporary table, and initiating transfer of the redistribution data portion to the at least one additional DN.

Abstract: A method for data redistribution of a job data in a first datanode (DN) to at least one additional DN in a Massively Parallel Processing (MPP) Database (DB) is provided. The method includes recording a snapshot of the job data, creating a first data portion in the first DN and a redistribution data portion in the first DN, collecting changes to a job data copy stored in a temporary table, and initiating transfer of the redistribution data portion to the at least one additional DN.

Abstract: Printable and stretchable thin-film devices and fabrication techniques are provided for forming fully-printed, intrinsically stretchable thin-film transistors and integrated logic circuits using stretchable elastomer substrates such as polydimethylsiloxane (PDMS), semiconducting carbon nanotube network as channel, unsorted carbon nanotube network as source/drain/gate electrodes, and BaTiO3/PDMS composite as gate dielectric. Printable stretchable dielectric layer ink may be formed by mixing barium titanate nanoparticle (BaTiO3) with PDMS using 4-methyl-2-pentanone as solvent.

Abstract: A computer-implemented method of relocating data in a distributed database comprises: creating, by one or more processors, a second table in the distributed database, the second table including all columns from a first table; copying, by the one or more processors, a first set of tuples from the first table to the second table; modifying, by the one or more processors, during the copying of the first set of tuples, data of the first table according to a modification; after the copying of the first set of tuples, modifying, by the one or more processors, data of the second table according to the modification; and switching, by the one or more processors, the second table for the first table in a catalog of the distributed database.

Abstract: Transaction processing for a database distributed across availability zones is disclosed, including: determining that a transaction comprising a set of one or more statements is to be executed on a plurality of database servers across at least two availability zones, wherein each availability zone is associated with a respective hybrid logical clock (HLC)-based centralized time service; causing the set of one or more statements to execute on the plurality of database servers across the at least two availability zones; obtaining a plurality of HLC-based prepare timestamps from the plurality of database servers across the at least two availability zones; selecting a maximum HLC-based prepare timestamp to use as a commit timestamp associated with the transaction; and determining whether to return a commit result corresponding to the transaction after a time delay that is determined based at least in part on a predetermined time skew.

Abstract: A system and method for improved online transaction processing (OLTP) in a sharded database is provided. Overhead associated with a global transaction manager is reduced and scalability improved by determining whether incoming queries are single-shard transactions or multi-shard transactions. For multi-shard transactions, a distributed transaction ID (DXID) is requested from the GTM, and then forwarded with the query to one or more data notes. For single-shard transactions, the query is sent to a data node without requesting a DXID from the GTM.

Abstract: A method for data redistribution of a job data in a first datanode (DN) to at least one additional DN in a Massively Parallel Processing (MPP) Database (DB) is provided. The method includes recording a snapshot of the job data, creating a first data portion in the first DN and a redistribution data portion in the first DN, collecting changes to a job data copy stored in a temporary table, and initiating transfer of the redistribution data portion to the at least one additional DN.

Abstract: A database system comprises a persistent storage device, a log node including a memory and a processor, and a plurality of database nodes. A database node includes a cache memory configured to store a database instance, and a processor configured to initiate a database transaction by sending a snapshot request to the log node, the snapshot request including a list of pages that were either replaced or newly loaded in the cache memory. The log node processor is configured to send a snapshot response to the database node, wherein the snapshot response includes a snapshot of the database and a list of changed pages of the database instances. The database node processor is configured to update the status of the pages in cached memory according to the snapshot response and perform the database transaction.

Abstract: A method for data redistribution of a job data in a first datanode (DN) to at least one additional DN in a Massively Parallel Processing (MPP) Database (DB) is provided. The method includes recording a snapshot of the job data, creating a first data portion in the first DN and a redistribution data portion in the first DN, collecting changes to a job data copy stored in a temporary table, and initiating transfer of the redistribution data portion to the at least one additional DN.

Abstract: A system (and associated method) includes a processor which determines a performance metric ratio of a performance metric of a second type of server relative to a performance metric of a first server type for each of multiple sizes of multiple benchmark datasets to thereby determine a plurality of performance metric ratio values. The processor also determines an interpolation function for the plurality of performance metric ratio values usable to compute interpolation performance metric ratios of the second type of server relative to the first type of server for dataset sizes other than the first plurality of sizes. Given a second dataset, the processor determines an amount of the second dataset to provide to each of the respective server types using the interpolation function. The processor configures a load balancer based on the amount of the second dataset determined for each type of server.

Abstract: A system and method for improved online transaction processing (OLTP) in a sharded database is provided. Overhead associated with a global transaction manager is reduced and scalability improved by determining whether incoming queries are single-shard transactions or multi-shard transactions. For multi-shard transactions, a distributed transaction ID (DXID) is requested from the GTM, and then forwarded with the query to one or more data notes. For single-shard transactions, the query is sent to a data node without requesting a DXID from the GTM.

Abstract: A computer-implemented method of relocating data in a distributed database comprises: creating, by one or more processors, a second table in the distributed database, the second table including all columns from a first table; copying, by the one or more processors, a first set of tuples from the first table to the second table; modifying, by the one or more processors, during the copying of the first set of tuples, data of the first table according to a modification; after the copying of the first set of tuples, modifying, by the one or more processors, data of the second table according to the modification; and switching, by the one or more processors, the second table for the first table in a catalog of the distributed database.

Abstract: Printable and stretchable thin-film devices and fabrication techniques are provided for forming fully-printed, intrinsically stretchable thin-film transistors and integrated logic circuits using stretchable elastomer substrates such as polydimethylsiloxane (PDMS), semiconducting carbon nanotube network as channel, unsorted carbon nanotube network as source/drain/gate electrodes, and BaTiO3/PDMS composite as gate dielectric. Printable stretchable dielectric layer ink may be formed by mixing barium titanate nanoparticle (BaTiO3) with PDMS using 4-methyl-2-pentanone as solvent.

Abstract: A system (and associated method) includes a processor which determines a performance metric ratio of a performance metric of a second type of server relative to a performance metric of a first server type for each of multiple sizes of multiple benchmark datasets to thereby determine a plurality of performance metric ratio values. The processor also determines an interpolation function for the plurality of performance metric ratio values usable to compute interpolation performance metric ratios of the second type of server relative to the first type of server for dataset sizes other than the first plurality of sizes. Given a second dataset, the processor determines an amount of the second dataset to provide to each of the respective server types using the interpolation function. The processor configures a load balancer based on the amount of the second dataset determined for each type of server.

Abstract: A computer-implemented method for distributing a plurality of data partitions among a cluster of computer nodes includes dividing a database into a plurality of primary partitions, storing the primary partitions on a plurality of nodes associated with a computer network, duplicating the primary partitions to create a plurality of secondary partitions and storing the secondary partitions on the nodes, wherein the primary and secondary partitions are substantially evenly distributed among the nodes, each secondary partition is stored on a different node than its corresponding primary partition, diversity exists with respect to each secondary partition and the node where it is stored, the primary partitions are available to serve a system workload, and one or more secondary partitions corresponding to one or more primary partitions of a failed node are available to be upgraded to primary status to maintain workload balancing and data availability after one of the computer nodes fails.

Abstract: A method includes dividing a dataset into partitions by hashing a specified key, selecting a set of distributed file system nodes as a primary node group for storage of the partitions, and causing a primary copy of the partitions to be stored on the primary node group by a distributed storage system file server such that the location of each partition is known by hashing of the specified key.