Abstract: A database is stored as a plurality of database shards in a distributed database grid comprising a plurality of grid elements, each including a mid-tier database system. A first grid element receives, from an application executing in the same memory as a mid-tier database system of the first grid element, a first database transaction including at least one database operation on specific data stored in a first database shard that belongs to the first grid element. The first grid element performs and commits the first database transaction without participation of another grid element of the plurality of grid elements. The first grid element receives a second database transaction that requires access to another database shard that does not belong to the first grid element. Multiple grid elements of the plurality of grid elements perform the second database transaction and commit the second database transaction using a two-phase commit protocol.

Abstract: In an in-memory database management system, non-volatile random access memories (NVRAMs) are used to store database data and control data. Because this data is stored in NVRAM, the data survives system failures. Recovery from a system failure may be accomplished more quickly by, at least in part, modifying the surviving data in NVRAM, rather than loading an entire checkpoint image and applying uncheckpointed transactions needed to synchronize the database. Because in this form of recovery the database state that serves as the starting point for applying change records is the database as stored in the NVRAM, this form of recovery is referred to herein as in-memory-based recovery. Recovery, where the database state that serves as the starting point for applying change records is a checkpoint image, is referred to herein as checkpointed-based recovery. In-memory-based recovery eliminates or reduces the need to perform certain operations that are performed for checkpointed-based recovery.

Abstract: Techniques are described for performing dependency locking to enable parallel execution of database server processes modifying the same object. In an embodiment, a DBMS receives a request to execute an operation on its managed database. The request may include an object identifier and a version identifier for a version of a database object, which is required for the successful execution of the operation on the database. The required version of the database object may not exist and may be generated only after the execution of another, second, operation on the database. The first database server process initiates execution of the earlier received operation on the database. The first database server process queries the first database for the version of the particular database object and determines that the version of the database object does not exist yet, in one embodiment.

Abstract: In column domain dictionary compression, column values in one or more columns are tokenized by a single dictionary. The domain of the dictionary is the entire set of columns. A dictionary may not only map a token to a tokenized value, but also to a count (“token count”) of the number of occurrences of the token and corresponding tokenized value in the dictionary's domain. Such information may be used to compute queries on the base table.

Abstract: In an in-memory database management system, non-volatile random access memories (NVRAMs) are used to store database data and control data. Because this data is stored in NVRAM, the data survives system failures. Recovery from a system failure may be accomplished more quickly by, at least in part, modifying the surviving data in NVRAM, rather than loading an entire checkpoint image and applying uncheckpointed transactions needed to synchronize the database. Because in this form of recovery the database state that serves as the starting point for applying change records is the database as stored in the NVRAM, this form of recovery is referred to herein as in-memory-based recovery. Recovery, where the database state that serves as the starting point for applying change records is a checkpoint image, is referred to herein as checkpointed-based recovery. In-memory-based recovery eliminates or reduces the need to perform certain operations that are performed for checkpointed-based recovery.

Abstract: Techniques are described for performing dependency locking to enable parallel execution of database server processes modifying the same object. In an embodiment, a DBMS receives a request to execute an operation on its managed database. The request may include an object identifier and a version identifier for a version of a database object, which is required for the successful execution of the operation on the database. The required version of the database object may not exist and may be generated only after the execution of another, second, operation on the database. The first database server process initiates execution of the earlier received operation on the database. The first database server process queries the first database for the version of the particular database object and determines that the version of the database object does not exist yet, in one embodiment.

Abstract: The disclosure provides a preparation method of a porous copper alloy wick, including the steps of: a) preparing an electrolyte, which is an aqueous solution including 0.5-1.8 mol/L sulfuric acid and 0.1-0.5 mol/L copper sulfate; b) cleaning with a mixed solution of a surfactant and a basic compound, activating with dilute hydrochloric acid and then cleaning the surface of a copper alloy substrate; c) forming a porous structure on the substrate by electrodeposition on the treated substrate in the electrolyte; and d) washing with water, drying and then sintering the product obtained in step c). By the method of the disclosure, the porous structure with the specific arrangement, excellent capillary force and permeability can be directly obtained on the surface of the substrate, which is good for the transmission of the working liquid.

Abstract: The disclosure provides a method for preparing a porous wick, including the steps of: a) preparing an first electrolyte, which is an aqueous solution including 0.5-1.8 mol/L sulfuric acid and 0.1-0.5 mol/L copper sulfate; b) preparing a second electrodeposition electrolyte, which is an aqueous solution including 0.2-0.9 mol/L sulfuric acid and 0.4-0.9 mol/L copper sulfate; c) cleaning the surface of a metal substrate with a mixed solution of a surfactant and a basic compound, activating with dilute hydrochloric acid, and then rinsing; and d) carrying out a first elctrodeposition on the treated substrate in the first electrodeposition electrolyte, and then carrying out the second electrodeposition in the second electrodeposition electrolyte, wherein the second electrodeposition current density is smaller than the first electrodeposition current density.

Abstract: A method, apparatus, and system for automatically determining an optimal database subsection is provided. A database subsection is selected to optimize certain benefits when the database subsection is translated, transferred, and cached on an alternative database system, which may utilize a different technology or database engine that provides certain performance benefits compared to the original database system. Algorithms such as multi-path greedy selection and/or dynamic programming may provide optimal or near-optimal results. A host for the alternative database server may be shared with or otherwise located in close physical proximity to improve latency for a database application or client layer. Once the database subsection analysis is completed, a report may be generated and presented to the user, and an implementation script may also be created to automatically configure a client host to function as a cache or replacement system according various cache size configurations described in the report.

Abstract: A plurality of mid-tier databases form a single, consistent cache grid for data in one or more backend data sources, such as a database system. The mid-tier databases may be standard relational databases. Cache agents at each mid-tier database swap in data from the backend database as needed. Ownership locks maintain consistency in the cache grid. Cache agents prevent database operations that will modify cached data in a mid-tier database unless and until ownership of the cached data can be acquired for the mid-tier database. Cache groups define what backend data may be cached, as well as a general structure in which the backend data is to be cached. Metadata for cache groups is shared to ensure that data is cached in the same form throughout the entire grid. Ownership of cached data can then be tracked through a mapping of cached instances of data to particular mid-tier databases.

Abstract: A database is stored as a plurality of database shards in a distributed database grid comprising a plurality of grid elements, each including a mid-tier database system. A first grid element receives, from an application executing in the same memory as a mid-tier database system of the first grid element, a first database transaction including at least one database operation on specific data stored in a first database shard that belongs to the first grid element. The first grid element performs and commits the first database transaction without participation of another grid element of the plurality of grid elements. The first grid element receives a second database transaction that requires access to another database shard that does not belong to the first grid element. Multiple grid elements of the plurality of grid elements perform the second database transaction and commit the second database transaction using a two-phase commit protocol.

Abstract: The present invention discloses a method for fabricating graphene, and comprises at least the following steps. First, a first electrode and a second electrode are inserted into an electrolyte without contacting. The first electrode is graphite, and the electrolyte comprises at least an ionic liquid. A potential difference will be produced between the first electrode and the second electrode to let the ionic liquid enter into each layer of the first electrode to form a plurality of graphene.

Abstract: A method, apparatus, and system for automatically determining an optimal database subsection is provided. A database subsection is selected to optimize certain benefits when the database subsection is translated, transferred, and cached on an alternative database system, which may utilize a different technology or database engine that provides certain performance benefits compared to the original database system. Algorithms such as multi-path greedy selection and/or dynamic programming may provide optimal or near-optimal results. A host for the alternative database server may be shared with or otherwise located in close physical proximity to improve latency for a database application or client layer. Once the database subsection analysis is completed, a report may be generated and presented to the user, and an implementation script may also be created to automatically configure a client host to function as a cache or replacement system according various cache size configurations described in the report.

Abstract: A semiconductor structure includes a carrier, a first protective layer, a second protective layer, and a third protective layer. A first surface of the first protective layer comprises a first anti-stress zone. A first extension line from a first bottom edge intersects with a second extension line from a second bottom edge to form a first base point. A first projection line is formed on the first surface, an extension line of the first projection line intersects with the second bottom edge to form a first intersection point, a second projection line is formed on the first surface, and an extension line of the second projection line intersects with the first bottom edge to form a second intersection point. A zone by connecting the first base point, the first intersection point and the second intersection point is the first anti-stress zone.

Abstract: A semiconductor structure includes a carrier, a first protective layer, a second protective layer, and a third protective layer. A first surface of the first protective layer comprises a first anti-stress zone. The second protective layer reveals the first anti-stress zone and comprises a second surface, a first lateral side, a second lateral side and a first connection side. The second surface comprises a second anti-stress zone. An extension line of the first lateral side intersects with an extension line of the second lateral side to form a first intersection point. A zone formed by connecting the first intersection point and two points of the first connection side is the first anti-stress zone. The third protective layer reveals the second anti-stress zone and comprises a second connection side projected on the first surface to form a projection line parallel to the first connection side.

Abstract: A semiconductor structure includes a carrier, a first protective layer, a second protective layer, and a third protective layer. A first surface of the first protective layer comprises a first anti-stress zone. The second protective layer reveals the first anti-stress zone and comprises a second surface, a first lateral side, a second lateral side and a first connection side. The second surface comprises a second anti-stress zone. An extension line of the first lateral side intersects with an extension line of the second lateral side to form a first intersection point. A zone formed by connecting the first intersection point and two points of the first connection side is the first anti-stress zone. The third protective layer reveals the second anti-stress zone and comprises a second connection side projected on the first surface to form a projection line parallel to the first connection side.

Abstract: A semiconductor structure includes a carrier, a first protective layer, a second protective layer, and a third protective layer. A first surface of the first protective layer comprises a first anti-stress zone. A first extension line from a first bottom edge intersects with a second extension line from a second bottom edge to form a first base point. A first projection line is formed on the first surface, an extension line of the first projection line intersects with the second bottom edge to form a first intersection point, a second projection line is formed on the first surface, and an extension line of the second projection line intersects with the first bottom edge to form a second intersection point. A zone by connecting the first base point, the first intersection point and the second intersection point is the first anti-stress zone.

Abstract: A system includes an active node and a standby node and zero or more replica nodes. Each of the nodes includes a database system, such as an in-memory database system. Client updates applied to the active node are written through to the standby node, and the standby node writes the updates through to a primary database and updates the replica nodes. Commit ticket numbers tag entries in transaction logs and are used to facilitate recovery if either of the active node or the standby node fails. Updates applied to the primary database are autorefreshed to the active node and written through by the active node to the standby node which propagates the updates to the replica nodes. Bookmarks are used to track updated records of the primary database and are used to facilitate recovery if either of the active node or the standby node fails.

Abstract: A method, apparatus, and system for automatically determining an optimal database subsection is provided. A database subsection is selected to optimize certain benefits when the database subsection is translated, transferred, and cached on an alternative database system, which may utilize a different technology or database engine that provides certain performance benefits compared to the original database system. Algorithms such as multi-path greedy selection and/or dynamic programming may provide optimal or near-optimal results. A host for the alternative database server may be shared with or otherwise located in close physical proximity to improve latency for a database application or client layer. Once the database subsection analysis is completed, a report may be generated and presented to the user, and an implementation script may also be created to automatically configure a client host to function as a cache or replacement system according various cache size configurations described in the report.

Abstract: A replication track is a designated group of transactions that are to be replicated at a destination database in a way that, with respect to any other transaction in the replication track, preserves transactional dependency. Further, transactions in a replication track can be replicated at the destination database without regard to transactional dependency of other transactions in another track. This facilitates concurrent parallel replication of transactions of different tracks. Replicating data in this manner is referred to herein as track replication. An application may request execution of transactions and designate different tracks for transactions.