Abstract: A method, a system and a computer program product for execution of queries. A first query is executed using a first query execution plan to generate a first result data by applying a first query operator to a first data stored in a first storage location. The first result data is provided to a second query execution plan for execution of a second query. The second query is executed on a second data stored in a second storage location in accordance with the second query execution plan. The second query execution plan includes a second query operator. Based on the execution of the second query, a second result data is generated in accordance with the second query execution plan by at least applying the second query operator to at least the provided first result data.

Abstract: A method, a system and a computer program product for executing management of ownership of data. An index in a plurality of indexes is selected. The index corresponds to a plurality of ranges of data values stored in a plurality of database slices of a database. The index further corresponds to a partitioning structure that includes a plurality of hierarchically arranged nodes. Each node corresponds to a range of data values stored in at least one database slice. The structure is replicated across a plurality of computing systems. A computing system executes an update to one or more ranges of data values. The system replicates at least one of a database slice including the updated ranges of data values and a node that includes the updated ranges of data values to another computing system for storage of a replicate of the updated ranges of data values.

Abstract: A node type of a plurality of distributed nodes to which a table to be added to a distributed database should be assigned can be identified by applying a set of placement rules defined for the table. The set of placement rules can also be applied to determine whether the table should be partitioned into more than one partition. A table group name associated with the table can be obtained and used in conjunction with the node type and determination of whether to partition the table to store the table in the distributed database on at least one node of the plurality of nodes as one or more partitions.

Abstract: In a general aspect, a method includes inserting a record in a partitioned fact table of a star schema data mart. Inserting the record can include determining a first hash value from a first dimension value of the record and determining a first set of candidate partitions from the first hash value. The method can further include determining a second hash value from a second dimension value of the record and determining a second set of candidate partitions from the first hash value. The method can further include comparing the first set of candidate partitions with the second set of candidate partitions to determine a common partition and inserting the record into the common partition.

Abstract: A method, a system and a computer program product for implicitly partitioning data. An index in a plurality of indexes is selected. The index corresponds to a plurality of ranges of data values stored in a plurality of database slices of a database. A partitioning structure for the selected index is generated. The partitioning structure includes a plurality of hierarchically arranged nodes. Each node corresponds to a range of data values in the plurality of ranges of data values stored and at least one database slice storing corresponding range of data values. Another range of data values is received for storage in the database. Using the partitioning structure, a node in the partitioning structure corresponding to the received range of data values and a corresponding database slice for storing the received range of data values are identified. The received range of data values is stored in the identified database slice.

Abstract: A node type of a plurality of distributed nodes to which a table to be added to a distributed database should be assigned can be identified by applying a set of placement rules defined for the table. The set of placement rules can also be applied to determine whether the table should be partitioned into more than one partition. A table group name associated with the table can be obtained and used in conjunction with the node type and determination of whether to partition the table to store the table in the distributed database on at least one node of the plurality of nodes as one or more partitions.

Abstract: A data storage and retrieval system for a computer memory configured according to a document store adapted to contain documents. The document store includes a document data structure containing a header and a document having one or more members. The document store further includes a chain of one or more differential data structures, each having a header and at least one updated member. The updated member has a value which is updated relative to a value in a corresponding member having a same identifier in the document data structure or in a preceding differential data structure in the chain. A header of each of the differential data structures includes a pointer to the document data structure or the preceding differential data structure in the chain, and a flag indicating that each of the differential data structures contains less than all of the members of the document data structure.

Abstract: Persisting data in logical tiers of an in-memory database based on aging rules of the database system. The database system can be configured to age data by moving the data from a first logical tier supporting high performance data access to a second logical tier supporting lower performance data access, thereby improving the operational efficiency of the database system.

Abstract: A method, a system and a computer program product for implicitly partitioning data. An index in a plurality of indexes is selected. The index corresponds to a plurality of ranges of data values stored in a plurality of database slices of a database. A partitioning structure for the selected index is generated. The partitioning structure includes a plurality of hierarchically arranged nodes. Each node corresponds to a range of data values in the plurality of ranges of data values stored and at least one database slice storing corresponding range of data values. Another range of data values is received for storage in the database. Using the partitioning structure, a node in the partitioning structure corresponding to the received range of data values and a corresponding database slice for storing the received range of data values are identified. The received range of data values is stored in the identified database slice.

Abstract: A method, a system and a computer program product for executing management of ownership of data. An index in a plurality of indexes is selected. The index corresponds to a plurality of ranges of data values stored in a plurality of database slices of a database. The index further corresponds to a partitioning structure that includes a plurality of hierarchically arranged nodes. Each node corresponds to a range of data values stored in at least one database slice. The structure is replicated across a plurality of computing systems. A computing system executes an update to one or more ranges of data values. The system replicates at least one of a database slice including the updated ranges of data values and a node that includes the updated ranges of data values to another computing system for storage of a replicate of the updated ranges of data values.

Abstract: A database system can receive, from a client, a query specifying at least one database operation implicating data within a first database and within a second database. The first database can have a first transaction manager and the second database can have a second transaction manager. Thereafter, a plurality of transactions are initiated that are responsive to the query to access the data within the first database and the second database. The first transaction manager and the second transaction manager together coordinate execution of the plurality of transactions. All changes specified by the at least one database operation are persisted in persistence of the first database including changes implicating data stored within the second database. Data responsive to the query can then optionally be provided to the client. Related apparatus, systems, techniques and articles are also described.

Abstract: A system for hash collision tables for relational operations is provided. In some implementations, the system performs operations comprising generating a plurality of hash values for at least a portion of one or more database tables based on a database query, and generating a hash table for at least a portion of the plurality of hash values. The operations can further include generating first results based on execution of a first operation in the database query using the hash table. Additionally, the operations can further include generating second results based on the first results and execution of a second operation in the database query using the hash table. Related systems, methods, and articles of manufacture are also described.

Abstract: A system for storage, access, and/or pruning of documents of a document store is provided. In some implementations, the system performs operations comprising analyzing a plurality of parameters of a plurality of documents stored among a plurality of slices in a database and generating, based on the analyzing, statistics about the plurality of parameters including a range of document identifiers present in corresponding slices from the plurality of slices. The operations can further comprise pruning, based on the statistics, one or more slices of the plurality of slices, the pruning triggered in response to a query related to at least a portion of the plurality of stored documents. The operations can further comprise responding to the query based on slices that are not pruned. One or more of the operations can be implemented by a database server. Related systems, methods, and articles of manufacture are also described.

Abstract: A system, a method, and a computer program product for providing transparent access to multi-temperature data are disclosed. A query for accessing data is received. The query includes at least one selection parameter for retrieval of data. The data is stored in a plurality of partitions of a database system. Each partition has a maximum data value per column, a minimum data value per column, and a predetermined date associated with the data contained in the partition. A determination is made whether at least one selection parameter is greater than the minimum data value per column and less than the maximum data value per column. The queried data is retrieved from the partition using the predetermined date associated with the data contained in the partition.

Abstract: A method can include: generating a query execution plan for a query including a plurality of operations that operate on data from a relational database and data from a non-structured query language (NoSQL) database, the generating comprising optimizing the query by: identifying a first operation that operate on data from the relational database and an intermediate result output by a second operation, the second operation outputting the intermediate result by operating on the data from the NoSQL database; and determining a fixed datatype for the intermediate result, an indication of the fixed datatype being included in the query execution plan; and executing, based on the query execution plan, the query, the executing of the query comprising converting the intermediate result to the fixed datatype, the converting enabling the first operation to operate on the intermediate result output by the second operation along with the data from the relational database.

Abstract: Technologies are described for facilitating database system recovery in a distributed database environment having a master node and at least one slave node. The master node maintains an in-memory reference that includes transaction identifiers and their corresponding commit identifiers. When a slave node requests that a commit identifier be assigned to a transaction, the transaction and commit identifiers for the transaction are added to the in-memory reference. The commit identifier is sent by the master node to the slave node. The slave node writes a log entry to a commit log that includes the transaction identifier and the assigned commit identifier. If the database system is interrupted before the slave node writes the commit log entry, the slave node can request the commit identifier for the transaction from the master node, which retrieves the identifier from the in-memory reference.

Abstract: Provided are systems and methods to acquire a manifest data file and a binary copy of a document store slice log having a first filename and comprising a plurality of entries, each of the plurality of entries associated with a respective database transaction and a commit identifier, and the manifest data file indicating one or more data partitions and one or more slices of each of the one or more data partitions, acquire a partition log for one of the indicated one or more data partitions, the generated partition log comprising a log entry associated with a transaction to create a slice and including a second filename associated with the slice, sort the plurality of entries of the document store slice log based on their associated commit identifiers, change the commit identifiers of each of the plurality of entries to a same commit identifier, and store the sorted and changed entries in a second document store slice log having the second filename.

Abstract: Provided are systems and methods for storing checkpoints of an in-memory storage device. In one example, the method may include detecting database transactions performed on a slice of an in-memory storage and storing a record of the database transactions in a log file, receiving a request to persist the slice of in-memory storage, the request comprising a timing indicator corresponding to a timing of database transactions, trimming the log file based on the timing indicator to remove a record of one or more database transactions from the log file that occurred prior to the timing indicator and to preserve a record of one or more database transactions that occurred after the timing indicator, and persisting, to disk, data from the slice of in-memory storage and the trimmed log file preserving the record of the one or more database transactions that occurred after the timing indicator.

Abstract: A system for encoding and/or decoding documents for a document store is provided. In some implementations, the system performs operations comprising receiving a query related to at least a portion of a plurality of stored documents and retrieving one or more documents from the plurality of stored documents based on the query. The operations can further include generating a client-side dictionary including a plurality of definitions corresponding to a plurality of parameters (e.g., reference values for corresponding parameters) from the plurality of stored documents. The operations can also include providing the client-side dictionary and the one or more documents in response to the query. One or more of the operations can be implemented by a database server. Related systems, methods, and articles of manufacture are also described.

Abstract: Technologies are described for facilitating database system recovery in a distributed database environment having a master node and at least one slave node. The master node maintains an in-memory reference that includes transaction identifiers and their corresponding commit identifiers. When a slave node requests that a commit identifier be assigned to a transaction, the transaction and commit identifiers for the transaction are added to the in-memory reference. The commit identifier is sent by the master node to the slave node. The slave node writes a log entry to a commit log that includes the transaction identifier and the assigned commit identifier. If the database system is interrupted before the slave node writes the commit log entry, the slave node can request the commit identifier for the transaction from the master node, which retrieves the identifier from the in-memory reference.