Abstract: A database-management system provides sargable evaluation for query predicates that compare an “LHS” encrypted database-column operand to an “RHS” expression operand. The system directly compares the two operands if all their attributes match. If the operands are encrypted string-type values differing only in length, the system truncates the RHS or pads it with encrypted blanks and, if a truncation loses meaningful data, evaluates the predicate as never satisfying an equality condition. In all other cases, if all attributes of a plaintext RHS don't match those of the plaintext data encoded into the LHS column, the system attempts to cast the RHS to match the plaintext LHS data. An error condition or data loss at this step allows the system to sargably evaluate the predicate without further analysis, but if the casting is successful and error-free, the system encrypts the resulting RHS and performs a sargable predicate evaluation.

Abstract: A computing system includes an application configured to request execution of at least one translation including at least one command. A first coupling facility is configured to perform a first modification process to modify a first structure based on a received command associated with an ongoing transaction. A second coupling facility includes a secondary circular queue loaded with first data blocks indicating the first modification process, and is configured to output a message response block (MRB). The application determines a most recent modification process performed by the secondary coupling facility based on the MRB.

Abstract: A database-management system provides sargable evaluation for query predicates that compare an “LHS” encrypted database-column operand to an “RHS” expression operand. The system directly compares the two operands if all their attributes match. If the operands are encrypted string-type values differing only in length, the system truncates the RHS or pads it with encrypted blanks and, if a truncation loses meaningful data, evaluates the predicate as never satisfying an equality condition. In all other cases, if all attributes of a plaintext RHS don't match those of the plaintext data encoded into the LHS column, the system attempts to cast the RHS to match the plaintext LHS data. An error condition or data loss at this step allows the system to sargably evaluate the predicate without further analysis, but if the casting is successful and error-free, the system encrypts the resulting RHS and performs a sargable predicate evaluation.

Abstract: A database-management system provides sargable evaluation for query predicates that compare an “LHS” encrypted database-column operand to an “RHS” expression operand. The system directly compares the two operands if all their attributes match. If the operands are encrypted string-type values differing only in length, the system truncates the RHS or pads it with encrypted blanks and, if a truncation loses meaningful data, evaluates the predicate as never satisfying an equality condition. In all other cases, if all attributes of a plaintext RHS don't match those of the plaintext data encoded into the LHS column, the system attempts to cast the RHS to match the plaintext LHS data. An error condition or data loss at this step allows the system to sargably evaluate the predicate without further analysis, but if the casting is successful and error-free, the system encrypts the resulting RHS and performs a sargable predicate evaluation.

Abstract: A business application may provide a secure ledger update while maintaining anonymity and security from unauthorized third parties. One example may include receiving a new entry transaction to save data in a database/ledger. The example may also include receiving a request to add a record stored in a database with a new entry, adding the record by inserting the new entry, and enabling the new entry to be unchangeable from subsequent modification attempts based on an immutable attribute.

Abstract: A computing system includes an application configured to request execution of at least one translation including at least one command. A first coupling facility is configured to perform a first modification process to modify a first structure based on a received command associated with an ongoing transaction. A second coupling facility includes a secondary circular queue loaded with first data blocks indicating the first modification process, and is configured to output a message response block (MRB). The application determines a most recent modification process performed by the secondary coupling facility based on the MRB.

Abstract: A database-management system provides sargable evaluation for query predicates that compare an “LHS” encrypted database-column operand to an “RHS” expression operand. The system directly compares the two operands if all their attributes match. If the operands are encrypted string-type values differing only in length, the system truncates the RHS or pads it with encrypted blanks and, if a truncation loses meaningful data, evaluates the predicate as never satisfying an equality condition. In all other cases, if all attributes of a plaintext RHS don't match those of the plaintext data encoded into the LHS column, the system attempts to cast the RHS to match the plaintext LHS data. An error condition or data loss at this step allows the system to sargably evaluate the predicate without further analysis, but if the casting is successful and error-free, the system encrypts the resulting RHS and performs a sargable predicate evaluation.

Abstract: A computing system includes an application configured to request execution of at least one translation including at least one command. A first coupling facility is configured to perform a first modification process to modify a first structure based on a received command associated with an ongoing transaction. A second coupling facility includes a secondary circular queue loaded with first data blocks indicating the first modification process, and is configured to output a message response block (MRB). The application determines a most recent modification process performed by the secondary coupling facility based on the MRB.

Abstract: A business application may provide a secure ledger update while maintaining anonymity and security from unauthorized third parties. One example may include receiving a new entry transaction to save data in a database/ledger. The example may also include receiving a request to add a record stored in a database with a new entry, adding the record by inserting the new entry, and enabling the new entry to be unchangeable from subsequent modification attempts based on an immutable attribute.

Abstract: A business application may provide a secure ledger update while maintaining anonymity and security from unauthorized third parties. One example may include receiving a new entry transaction to save data in a database/ledger. The example may also include receiving a request to add a record stored in a database with a new entry, adding the record by inserting the new entry, and enabling the new entry to be unchangeable from subsequent modification attempts based on an immutable attribute.

Abstract: A computing system includes an application configured to request execution of at least one translation including at least one command. A first coupling facility is configured to perform a first modification process to modify a first structure based on a received command associated with an ongoing transaction. A second coupling facility includes a secondary circular queue loaded with first data blocks indicating the first modification process, and is configured to output a message response block (MRB). The application determines a most recent modification process performed by the secondary coupling facility based on the MRB.

Abstract: A business application may provide a secure ledger update while maintaining anonymity and security from unauthorized third parties. One example may include receiving a new entry transaction to save data in a database/ledger. The example may also include receiving a request to add a record stored in a database with a new entry, adding the record by inserting the new entry, and enabling the new entry to be unchangeable from subsequent modification attempts based on an immutable attribute.

Abstract: A method for managing a cache structure of a coupling facility includes receiving a conditional write command from a computing system and determining whether data associated with the conditional write command is part of a working set of data of the cache structure. If the data associated with the conditional write command is part of the working set of data of the cache structure the conditional write command is processed as an unconditional write command. If the data associated with the conditional write command is not part of the working set of data of the cache structure a conditional write failure notification is transmitted to the computing system.

Abstract: A method for managing a cache structure of a coupling facility includes receiving a conditional write command from a computing system and determining whether data associated with the conditional write command is part of a working set of data of the cache structure. If the data associated with the conditional write command is part of the working set of data of the cache structure the conditional write command is processed as an unconditional write command. If the data associated with the conditional write command is not part of the working set of data of the cache structure a conditional write failure notification is transmitted to the computing system.

Abstract: A method for managing a cache structure of a coupling facility includes receiving a conditional write command from a computing system and determining whether data associated with the conditional write command is part of a working set of data of the cache structure. If the data associated with the conditional write command is part of the working set of data of the cache structure the conditional write command is processed as an unconditional write command. If the data associated with the conditional write command is not part of the working set of data of the cache structure a conditional write failure notification is transmitted to the computing system.

Abstract: A method for managing a cache structure of a coupling facility includes receiving a conditional write command from a computing system and determining whether data associated with the conditional write command is part of a working set of data of the cache structure. If the data associated with the conditional write command is part of the working set of data of the cache structure the conditional write command is processed as an unconditional write command. If the data associated with the conditional write command is not part of the working set of data of the cache structure a conditional write failure notification is transmitted to the computing system.

Abstract: Coupling facility store-in cache structures are duplexed in order to improve data availability. That is, once duplexing is established, selective data is written to both a primary structure instance and a secondary structure instance. Thus, if one of the structure instances fails, then the other structure instance is used in order to prevent data from being lost. Duplexing can be started manually and/or automatically by the operating system. Further, a structure may be removed from duplex mode and enter simplex mode, if duplexing is not desired.

Abstract: Castout processing for duplexed data structures. A selective data item is written from a primary instance of a data structure to at least one storage medium. A determination is made as to whether the selective data item can be deleted from a secondary instance of the data structure. If the selective data item can be deleted, it is deleted from the secondary instance.

Abstract: Changed data of castout classes of a coupling facility cache are managed in order to be able to efficiently determine the age of the oldest changed data in the cache. A directory entry representing a changed datum is placed in a data structure corresponding to the castout class of the changed datum. The data structure includes an order queue ordered by timestamps and a process queue, having an ordered portion and an unordered portion. When the directory entry is to be added to the data structure, an attempt is first made to place the entry on the order queue. If the entry is not placed on the order queue within a predefined amount of time, then the entry is placed on the process queue, the order of which is maintained by background tasks. In order to return the oldest entry of the data structure, the smallest entry of the process queue is determined and that entry is then compared to the smallest entry of the order queue. The smaller of those two entries corresponds to the oldest entry for the castout class.

Abstract: An efficient procedure for determining the set of buffer pool database pages that must be externalized to stable storage and for scheduling their write I/O's before release of a committing transaction's locks. In a multisystem database management system (DBMS) with high-speed shared external storage (SES) environment, a DBMS instance may follow "force-at-commit" protocol for a database that has intersystem read/write interest or may alternatively follow a "no-force-at-commit" policy when operating with a database for which only one system has interest. By introducing the concept of a series of unique ordinal numbers (ORD#) for each database assigned to buffer pool data pages whenever the page state changes from clean to dirty within a single DBMS instance, this procedure maintains a transaction page list (TPL) for each transaction in ORD# order.