摘要:
Provided is a method, system, program, and data structures for making data available to an application program. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. The result table includes, for each row, a location identifier of the corresponding row in the base table and a column for each column in a query select list. The result table is accessed to return requested data from the base table to the application program.
摘要:
Traditional update semantics are provided when updates change the location of records in a database. The system detects that an update to a record will cause the record to change locations in a database from an original location to an updated location. The system selectively prevents activity in the database between the original location and update location until the updated record has changed locations in the database from the original location to the updated location.
摘要:
Provided is a method, system, program, and data structures for making data available to an application program. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. The result table includes, for each row, a location identifier of the corresponding row in the base table and a column for each column in a query select list. The result table is accessed to return requested data from the base table to the application program.
摘要:
Provided is a method, system, program, and data structures for making data available to an application program. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. The result table includes, for each row, a location identifier of the corresponding row in the base table and a column for each column in a query select list. The result table is accessed to return requested data from the base table to the application program.
摘要:
A method, apparatus, and article of manufacture for a computer implemented data manager. A statement is executed in a computer. The statement being performed by the computer to access data from a database stored on a data storage device connected to the computer. A determination is made as to whether to defer referential integrity checking when executing the statement. When it is determined that referential integrity checking is to be deferred, each record is processed that is specified in the statement. Keys for select records are stored as each record is processed. Then, after executing the statement, referential integrity checking is performed on the stored keys.
摘要:
A system and a method are described for selectively locking the partitions of a partitioned table in a relational database. The database system locks only those partitions of the table that are accessed by an application. Other partitions are available for concurrent access by other applications, regardless of the strength of the lock needed.
摘要:
Provided is a method, system, and program for performing a cursor operation. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. A command is received to perform a cursor operation with respect to a subject row in the result table. A lock is obtained on a row in the base table corresponding to the subject row in the result table. An operation specified in the received command is performed with respect to the subject row after obtaining the lock. The lock on the row in the base table is released after performing the operation.
摘要:
Provided are a method, system, and program for making data available to an application program. A cursor is generated positioned with respect to a result table, wherein the cursor specifies a search criteria, and wherein the result table includes rows from a base table that satisfy the search criteria. A fetch request is received indicating to position the cursor on a plurality of rows of the result table. The cursor is positioned on the plurality of rows of the result table indicated in the fetch request that satisfy the search criteria.
摘要:
Provided is a method, system, program, and data structures for making data available to an application program. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. The result table includes, for each row, a location identifier of the corresponding row in the base table and a column for each column in a query select list. The result table is accessed to return requested data from the base table to the application program.
摘要:
A primary database's log records are used to update a second database that has a different encoding scheme than the log record and the primary database. This encoding scheme, for example, may involve compression, encryption, or another data transformation. First, a stale encoded data record from the second database is identified. This data record is one whose counterpart in the primary database has been updated in the primary database and where update has been logged. The stale data record is modified to reflect its contents as encoded by the first encoding scheme rather than the second. Then, the logged change is applied to update the modified record. The updated record is then decoded and subsequently re-encoded according to the second encoding scheme. This record is then stored in the second database replacing the stale second data record.