Abstract: A computer implemented method for managing buffer pool usage includes identifying a database comprising one or more buffer pools and a set of database objects, adding a virtual layer between the set of database objects and the one or more buffer pools, wherein the virtual layer is configured to manage buffer pool resource utilization, managing, using the added virtual layer, buffer pool resource utilization with respect to the set of database objects, wherein the managing comprises defining buffer pool usage corresponding to the set of database objects, dynamically mapping database objects to the buffer pools based, at least in part, on the defined buffer pool usage, analyzing, by one or more processors, queues to identify updated buffer pool usage, and adjusting database object allocation according to the identified updated resource usage. A computer program product and computer system corresponding to the method are also disclosed.

Abstract: A method includes training, by a computing device, a model to identify SQL queries; identifying, by the computing device, incoming SQL queries; grouping, by the computing device, the incoming SQL queries into groups; monitoring, by the computing device, resource usage of the incoming SQL queries in the groups; and allocating, by the computing device, resources to an SQL query of the incoming SQL queries based on the monitoring.

Abstract: A simulated dataset is queried for regression by validating a structured query language (SQL) statement, determining a pattern type of the SQL statement, reconstructing the SQL statement according to a predetermined process for the pattern type, creating a mutated SQL statement for querying a simulated dataset, and validating the mutated SQL statement. The simulated dataset is based on a confidential dataset having the confidential elements removed or replaced.

Abstract: A computer-implemented method to generate and utilize a hybrid index. The method includes receiving a first query, where the first query is configured to perform a first command. The method further includes generating a hybrid index, where the hybrid index defines a connection between a first table and a second table of a set of tables. The method also includes executing the first query using the hybrid index. The method includes returning a set of results for the first query to a source of the query.

Abstract: A computer-implemented method, system and computer program product for improving performance of a distributed database. A query is received to store version data in the distributed database. Upon receiving the query to store the version data, the version data is stored in a row of a data page of a main table of a heap organized table/index organized table of the distributed database, where the row of the data page of the main table of the heap organized table/index organized table of the distributed database contains a pointer pointing to a later/previous version of the version data if the later/previous version of the version data is stored in the data page thereby chaining version data bi-directionally.

Abstract: A computer implemented method manages a location of database object descriptions in a storage, the computer implemented method. A number of processor units identifies a set of workload groups that are coming up for execution. The number of processor units loads the database object descriptions for the set of workload groups into a highest performance storage in a storage system. The number of processor units manages the location of the database object descriptions in the storage system based on access to database objects by set of workload groups.

Abstract: A method, system, and computer program product for abnormal data detection. According to the method, a plurality of data points collected at different time points are classified into a plurality of groups. A plurality of groups of potential abnormal data points are determined from the plurality of groups. Correlations between a first group of the plurality of groups of potential abnormal data points with other groups of potential abnormal data points are determined. In response to the first group of the plurality of groups of potential abnormal data points being uncorrelated to a majority of the other groups of potential abnormal data points based on the correlations, data points in the first group are identified as abnormal data points.

Abstract: One or more computer processors match a query pattern to a received query; context information related to the received query; retrieve a set of query records including the same context information as the obtained context information from an index knowledge base, wherein each query record in the set of query records include context information related to a respective history query, the query pattern, an index type associated with the query pattern, and performance information relating to the query pattern and the index type; determine that a subset of the retrieved query records includes one or more query patterns equivalent to the matched query pattern; select a query pattern and an associated index type from the subset of query records based on associated performance information in the set of query records; and perform the received query by applying the selected query pattern and the associated index type.

Abstract: Processing range operation data management statements in a database is provided. The method comprises receiving statements for range operations that specify referenced pages in the database. The range operations are stored in a search structure in a table directory in the database and applied to any referenced pages in a memory buffer pool. Application of the range operations is postponed for any referenced pages not in the memory buffer pool. The database determines if reading the postponed pages into the buffer pool would exceed a specified input/output threshold. If reading the postponed pages into the buffer pool does not exceed the specified threshold, the database reads the postponed pages from disk to the buffer pool asynchronously in parallel, and the range operations are then applied to the postponed pages. Pages modified by the range operations are then written from the buffer pool back to disk.

Abstract: Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: receiving an incoming query statement, wherein the incoming query statement comprises a query statement expression that includes an input variable; predicting an input variable value associated to the input variable; selecting an access path for runtime execution of the query statement in dependence on the predicted input variable value; and performing runtime execution of the query statement using the selected access path.

Abstract: A method of managing a storage system comprises detecting a reference to a first page in the storage system. The method also comprises creating a first candidate block for the first page based on the detecting. The first candidate block may comprise a continuous series of pages that begins with the first page. The method also comprises monitoring subsequent references to pages within the first candidate block. The method also comprises determining that the first candidate block meets a first set of hot-block requirements. The method also comprises relocating the first candidate block to a hot-block space in a buffer pool based on the determining, resulting in a first hot block.

Abstract: Modifying an index for a database is provided. An index tree for the database is traversed by: identifying a next node in the index tree, requesting a lock of the next node in the index tree, responsive to locking of the next node in the index tree, releasing a lock of a current node of the index tree, and making the next node in the index tree the current node of the index tree, until the current node of the index tree is a leaf node of the index tree. Responsive to determining to split the leaf node, the lock of the leaf node is released and, after releasing the lock of the leaf node, a lock of a non-leaf node parent of the leaf node in the index tree is requested.

Abstract: A computer implemented method processes a query. A number of processor units processes the query to identify a result set in response to receiving the query from a first client. The number of processor units stores, the result set in a shared cache assigned to a group of clients, wherein result set stored in the shared cache is accessible by the group of clients. The number of processor units returns the result set to a second client in the group of clients from the shared cache in response to receiving the query from the second client in the group of clients.

Abstract: A computer-implemented method, system and computer program product for handling lock contentions of an index (e.g., SQL index). Leaf pages of an index are monitored for a lock contention during an insert operation of index keys by the transactions. Upon detecting a lock contention of a leaf page, the next index key to be inputted into such a leaf page is routed to a queue of a buffer. The index key that was stored in the queue of the buffer is then mapped to the particular leaf page experiencing the lock contention where the transaction originally attempted to store such an index key, where such mapping is stored in a data structure. Upon such a leaf page no longer experiencing a lock contention, the appropriate index keys are then removed from the buffer and stored in the appropriate leaf page based on the mapping identified in the data structure.

Abstract: A computer-implemented method masks shard operations in a distributed database. The method includes performing a shard operation on a first table with a first column and a second column, where the shard operation divides the first table into a first shard with the first column and a second shard with the second column. The method also includes receiving a query, where the query is configured to perform at least a first command. The method further includes determining the first command is directed to the first column. The method includes updating the query to access the first shard in place of the first table. The method also includes executing the query and returning a set of results for the query to a source of the query.

Abstract: Modifying an index for a database is provided. An index tree for the database is traversed by: identifying a next node in the index tree, requesting a lock of the next node in the index tree, responsive to locking of the next node in the index tree, releasing a lock of a current node of the index tree, and making the next node in the index tree the current node of the index tree, until the current node of the index tree is a leaf node of the index tree. Responsive to determining to split the leaf node, the lock of the leaf node is released and, after releasing the lock of the leaf node, a lock of a non-leaf node parent of the leaf node in the index tree is requested.

Abstract: A computer implemented method for identifying problematic database operations includes identifying database transactions which exhibit performance issues and corresponding parse trees, transforming corresponding parse trees to create historical descriptor arrays, detecting a new database transaction, generating a new descriptor array corresponding to the new database transaction, analyzing the new descriptor array and the historical descriptor arrays to determine whether the new descriptor array indicates a performance issue corresponding to the new database transaction, and responsive to determining that the new descriptor array indicates a performance issue, adding the new database transaction to a resource controlled pool. The method may additionally comprise encoding one or more data items associated with the database.

Abstract: A method includes receiving, by a computing device, a Structured Query Language (SQL) query from a user; generating, by the computing device, execution structures from the SQL query; generating, by the computing device, test results by running the SQL query with the execution structures; building, by the computing device, logs which record information of the running of the SQL query; generating, by the computing device, a candidate execution structure using the information from the logs; normalizing, by the computing device, the SQL query using the candidate execution structure; running, by the computing device, the normalized SQL query in a database; and comparing, by the computing device, results of the normalized SQL query to the test results.

Abstract: A computer implemented method processes a search query from a requestor. A number of processor units selects an access path from access paths for each database in a set of databases based on reducing a cost for searching the set of databases using a set of access paths selected for the set of databases in response to receiving the search query from a requestor. The number of processor units receives a result set from searching the set of databases using the set of access paths selected for the set of databases. The number of processor units removes a number of duplicate records from records in the result set. The number of processor units sends the result set with the number of duplicate records removed to the requestor.

Abstract: A computer-implemented method improves the performance of write ahead logging. The method includes generating a set of query data and a set of log data, where the set of log data is configured to create a write ahead log, and the set of query data is configured to make changes to data in a database. The method also includes writing the set of query data to a virtual file system. The method further includes separating the set of log data into a set of control intervals, where each control interval includes an entry. The method includes writing, each entry into a log buffer, where the writing the set of query data to the virtual file system and the writing each entry into the log buffer are performed in parallel. The method also includes combining each entry into a complete log.