摘要:
A system and computer readable medium for executing a query to access data stored in a database, wherein the query includes a plurality of DISTINCT keys, is disclosed. The system and computer readable medium includes a capture module for identifying each of the plurality of DISTINCT keys in the query and a sort module coupled to the capture module for determining if more than one sort is needed to execute the query, performing a first DISTINCT operation on a first DISTINCT key of the plurality of DISTINCT keys, storing data fetched from the first DISTINCT operation in a master workfile only if more than one sort process is needed to execute the query, and utilizing the master workfile to perform subsequent DISTINCT operations on the other of the plurality of DISTINCT keys.
摘要:
A method for executing a query to access data stored in a database, wherein the query includes a plurality of DISTINCT keys, is disclosed. The method of the present invention includes providing a first DISTINCT operation on a first DISTINCT key, storing data fetched from the first DISTINCT operation in a master workfile if more than one sort process is needed to execute the query, and utilizing the master workfile to perform subsequent DISTINCT operations for the other DISTINCT keys.
摘要:
A system and computer readable medium for executing a query to access data stored in a database, wherein the query includes a plurality of DISTINCT keys, is disclosed. The system and computer readable medium includes a capture module for identifying each of the plurality of DISTINCT keys in the query and a sort module coupled to the capture module for determining if more than one sort is needed to execute the query, performing a first DISTINCT operation on a first DISTINCT key of the plurality of DISTINCT keys, storing data fetched from the first DISTINCT operation in a master workfile only if more than one sort process is needed to execute the query, and utilizing the master workfile to perform subsequent DISTINCT operations on the other of the plurality of DISTINCT keys.
摘要:
Disclosed is method for processing an aggregate function. Rows that contain a reference to intermediate result structures are grouped to form groups. For each group, aggregate element structures are formed from the intermediate result structures and, if the aggregate function specifies ordering, the aggregate element structures are sorted based on a sort key.
摘要:
Disclosed is a method, system, and program for processing an aggregate function. Rows that contain a reference to intermediate result structures are grouped to form groups. For each group, aggregate element structures are formed from the intermediate result structures and, if the aggregate function specifies ordering, the aggregate element structures are sorted based on a sort key.
摘要:
Disclosed is a method, system, and program for processing a function. A set of nested functions are received. A composite function is generated for the set of nested functions. A tagging template is generated for the set of nested functions that corresponds to the composite function. A result is produced by evaluating the composite function using the tagging template.
摘要:
A base table and related auxiliary table spaces are reorganized concurrently via a database utility. The database utility determines which auxiliary tables are related to the base table and automatically includes their respective auxiliary table in the same invocation of the utility. The reorganization is performed via allocated shadow data sets. The original data sets are switched with the newly built shadow data sets including the LOB shadows.
摘要:
A base table and related auxiliary table spaces are reorganized concurrently via a database utility. The database utility determines which auxiliary tables are related to the base table and automatically includes their respective auxiliary table in the same invocation of the utility. The reorganization is performed via allocated shadow data sets. The original data sets are switched with the newly built shadow data sets including the LOB shadows.