Abstract: A computer maps a literal in a database query to a digital representation, wherein the database query comprises a predicate, the literal is a part of the predicate, and the digital representation is predetermined based at least in part on external statistical data. The computer estimates a filter factor for the predicate based at least in part on the digital representation and compressed statistical data, wherein the compressed statistical data are prepared at least in part from the external statistical data.

Abstract: In managing multiple versions of triggers, a database system creates a first version of a trigger to apply a first set of actions in response to a first triggering event, which includes: creating a first package for the first version of the trigger to include the first set of actions; linking the first package to the database object; and setting the first package as a current version of the trigger. The database system creates a second version of the trigger to apply a second set of actions to the database object in response to a second triggering event, which includes: creating a second package for the second version of the trigger to include the second set of actions; and linking the second package to the database object. In response to a command, the database system sets the current version of the trigger to the second package.

Abstract: A method, system and computer program product for providing consolidated access to data of a plurality of source databases. Tables of each of the source databases are replicated to a shared accelerator. The source DBMSs are configured to dispatch queries to the accelerator for accelerating query execution. The accelerator is configured such that the replicated tables can only be accessed by the source DBMS having provided said tables for executing a dispatched query. A user can select one of the source DBMSs to act as a consolidated DBMS—C-DBMS. The C-DBMS provides the consolidated access. The user is enabled to select tables managed by another one of the DBMSs. In response to receiving the selection of the tables, the accelerator is re-configuring such that the C-DBMS is granted access also to the copies of the selected tables in the accelerator.

Abstract: A distributed database system (or federated database system) where a catalogue is used to store metadata descriptive of data containers for the constituent database system(s) and/or accelerator system(s) of the federated database. In response to the generation of the trigger signal corresponding to a database definition language (DDL) statement, the accelerator system updates metadata in the catalogue.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: A method, system and computer program product for providing consolidated access to data of a plurality of source databases. Tables of each of the source databases are replicated to a shared accelerator. The source DBMSs are configured to dispatch queries to the accelerator for accelerating query execution. The accelerator is configured such that the replicated tables can only be accessed by the source DBMS having provided said tables for executing a dispatched query. A user can select one of the source DBMSs to act as a consolidated DBMS—C-DBMS. The C-DBMS provides the consolidated access. The user is enabled to select tables managed by another one of the DBMSs. In response to receiving the selection of the tables, the accelerator is re-configuring such that the C-DBMS is granted access also to the copies of the selected tables in the accelerator.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: In an enforcement of temporal referential integrity in a database system, the database system receives a change request for one or more rows in a target table in the database system. The system determines that the target table has temporal referential constraints with a second table. The system compares a non-period child key value in child table row(s) with a non-period parent key value in parent table row(s) and compares a child business time period key value in the child table row(s) with a parent business time period key value in the parent table row(s). When the non-period child key value matches the non-period parent key value and when the child business time period key value is within the parent business time period key value, the system determines that the change request satisfies the temporal referential constraints. Otherwise, the system determines that the change request violates the temporal referential constraints.

Abstract: In an enforcement of temporal referential integrity in a database system, the database system receives a change request for one or more rows in a target table in the database system. The system determines that the target table has temporal referential constraints with a second table. The system compares a non-period child key value in child table row(s) with a non-period parent key value in parent table row(s) and compares a child business time period key value in the child table row(s) with a parent business time period key value in the parent table row(s). When the non-period child key value matches the non-period parent key value and when the child business time period key value is within the parent business time period key value, the system determines that the change request satisfies the temporal referential constraints. Otherwise, the system determines that the change request violates the temporal referential constraints.

Abstract: A database system searches for any statements that satisfy one or more of a set of filtering criteria. When a given dynamic query statement fully satisfies the set of filtering criteria, the given statement is stabilized by persistently storing a bound form of the given dynamic query statement. When the given dynamic query statement partly satisfies the set of filtering criteria, a monitoring request is created with the set of filtering criteria to begin monitoring subsequent executions of the statement, and the statement is linked to the monitoring request. When the given dynamic query statement subsequently fully satisfies the set of filtering criteria, the statement is stabilized by persistently storing the bound form of the statement. When the given dynamic query is re-executed, the stabilized statement is loaded, and the PREPARE process is bypassed.

Abstract: A row is inserted in a database table on a page having a first space reserved for inserting rows of the database table. A second space is reserved for adding data to the inserted row, wherein reserving the second space includes reserving the second space on the page responsive to inserting the row, so that the amount of space reserved for adding data to inserted rows grows as more rows are inserted. The page is marked full for the second space independently of whether the first space is full for inserting new rows. Data is added to rows on the page, responsive to detecting that the second space is full, by adding the data to one or more new pages, even though rows may still be inserted on the page using any remaining room in the first space on the page.

Abstract: In managing multiple versions of triggers, a database system creates a first version of a trigger to apply a first set of actions in response to a first triggering event, which includes: creating a first package for the first version of the trigger to include the first set of actions; linking the first package to the database object; and setting the first package as a current version of the trigger. The database system creates a second version of the trigger to apply a second set of actions to the database object in response to a second triggering event, which includes: creating a second package for the second version of the trigger to include the second set of actions; and linking the second package to the database object. In response to a command, the database system sets the current version of the trigger to the second package.

Abstract: In supporting temporal logical transactions, a database management system (DBMS) determines that a temporal logical transaction time (T) is set for a temporal logical transaction. The DBMS receives a change request for a current row in a current table. A history row for a history table corresponding to the current table is created. The values in the history row are set to the values in the current row, where a begin time in the history row has same value as a begin time in the current row, and an end time in the history row is set to T. When the begin time equals the end time in the history row, the DBMS does not store the history row in the history table. The values in the current row are changed according to the change request, and the begin time in the current row is set to T.

Abstract: In supporting temporal logical transactions, a database management system (DBMS) determines that a temporal logical transaction time (T) is set for a temporal logical transaction. The DBMS receives a change request for a current row in a current table. A history row for a history table corresponding to the current table is created. The values in the history row are set to the values in the current row, where a begin time in the history row has same value as a begin time in the current row, and an end time in the history row is set to T. When the begin time equals the end time in the history row, the DBMS does not store the history row in the history table. The values in the current row are changed according to the change request, and the begin time in the current row is set to T.

Abstract: A computer maps a literal in a database query to a digital representation, wherein the database query comprises a predicate, the literal is a part of the predicate, and the digital representation is predetermined based at least in part on external statistical data. The computer estimates a filter factor for the predicate based at least in part on the digital representation and compressed statistical data, wherein the compressed statistical data are prepared at least in part from the external statistical data.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.

Abstract: A first compute node of a plurality of compute nodes of a database cluster may receive a request for a database transaction from a client application. The client application may be located within the first compute node. A first connection may be established, without regard to whether another compute node has a lighter workload than the first compute node, between the client application and a first database of the database cluster. The first connection may be a local connection, wherein the first database is located within the first compute node. The first compute node may detect that a failure associated with the first database has occurred. The first compute node may execute a failover operation to continue servicing the request for the data. The executing of a failover operation may include establishing a second connection between the client application and a second database of the database cluster.