摘要:
A method and apparatus for receiving objects is provided. Embodiments provide for receiving, from a source database server, at a target database server, an object. If the object type of the object is involved in an inheritance hierarchy, then the target database server inspects the object to determine a source identifier that identifies to a source database server the object type associated with the object. The target database determines a target identifier that identifies to the target database server the object type associated with the object based on a mapping that associates source identifiers to target identifiers. Alternately, if the object type of the object is not involved in an inheritance hierarchy, then the target database server inspects the object to determine a set of characteristics of the object. The target database server determines the target identifier for the object based on the characteristics of the object.
摘要:
Techniques for migrating duration trees from a source database server (or instance) to a destination database server (or instance) are provided. A duration is a memory management construct that allows database components to group related areas of memory together. A source duration tree is captured at the source database server and combined with a destination duration tree at the destination database server. Any duration identifiers in the source duration tree that conflict with (i.e., are the same as) a duration identifier in the destination duration tree are mapped to new duration identifiers.
摘要:
Techniques for migrating duration trees from a source database server (or instance) to a destination database server (or instance) are provided. A duration is a memory management construct that allows database components to group related areas of memory together. A source duration tree is captured at the source database server and combined with a destination duration tree at the destination database server. Any duration identifiers in the source duration tree that conflict with (i.e., are the same as) a duration identifier in the destination duration tree are mapped to new duration identifiers.
摘要:
A computer automatically identifies multiple occurrences of an abstract data type that is embedded within an object of metadata of another abstract data type (hereinafter “top-level” abstract data type), e.g. by recursively visiting each element of the top-level abstract data type. Then the computer automatically generates, for the top-level abstract data type, a tap-level description that contains a description of each embedded abstract data type. At several locations in the top-level description that correspond to occurrences of a given embedded abstract data type in the top-level abstract data type, the computer automatically inserts offsets that identify a common position where the single description of that given embedded abstract data type is present in the tap-level description. Use of multiple offsets that identify a common position of an embedded description reduces space. The space was otherwise occupied by multiple embedded descriptions in prior art's top-level descriptions.
摘要:
Multiple groups of read-only files, for use by various components of an application program in a computer, are packaged as follows. Several executable files are prepared, each executable file corresponding to a group of read-only files used by one or more components. Each executable file includes an array that has sufficient space to accommodate the group of read-only files to be packaged therein. Each array in each executable file is overwritten with data from a corresponding group of read-only files. The presence or absence of each executable file for a group of read-only files is indicated by an index that is developed during initialization of components. Retrieval of data is from the executable files, if the index indicates, on first accessing each read-only file, that the corresponding executable file is present. If the executable file is indicated by the index as being absent, then the read-only file is directly accessed.
摘要:
Files of software to be installed in a computer are packaged as follows. A source file is prepared to contain at least a declaration of an array of sufficient space to accommodate the files to be packaged. The source file is compiled into an executable file. Thereafter, the array in the executable file is overwritten with data from each file being packaged. Depending on the embodiment, the address of where each file begins in the executable file and each file's name may be stored in the same executable file or in a different file. The stored file names are used to identify an address of a file from its name, when the named file is first accessed. In several embodiments, the operating system loads the executable file as a library that is automatically shared by multiple instances of the application (or by multiple applications), to efficiently use physical memory.