摘要:
Several embodiments of the present invention are directed to systems and methods for extending the UDT framework of an extended relational data store (ERDS) to include support for unordered collections (multisets) and ordered collection (lists). More specifically, several embodiments of the present invention use an UDT infrastructure, CLR generics, and a new UNNEST operator to create and utilize a special type abstraction for collections that is simultaneously a scalar and a relation. As a scalar, this collection type can be processed by all parts of the data store engine that understand scalars (including but not limited to the client stack) and, as a relation, this collection type is queriable like any other type of relation.
摘要:
Systems and methodologies of partially deserializing a Complex Type Object, via a deserializer that intercepts and materializes such object on demand. The object or a subset thereof can be deserialized to produce an Instance of Complex Type that is implemented by a property store. The deserializer can include an analyzer component that analyzes the Property Store.
摘要:
Various embodiments of the present invention are directed to a database with an extensible type system for at least one user-defined type that comprises information for describing its structure as well as information for describing an inheritance relationship between itself and another user-defined type (either a subtype or a supertype/base type). For certain embodiments, the user-defined type is defined in something other than Sequential Query Language (SQL) statement such as, for example, a Common Language Runtime (CLR) statement, a statement in C, C++, and C# (“C-sharp”), and/or a visual basic statement. In any event, several embodiments are further directed to a system wherein the database is aware of the inheritance relationship between two user-defined types by an explicit registration of the user-defined types with said database.
摘要:
A new persistence format for storing objects of a user defined type in a database store enables information about the structure of the type to be communicated to the store. This information enables a number of store optimizations, including direct structural access to members of the type. Specifically, metadata is exchanged between the type implementer and the data store. The store uses the metadata to determine the storage layout for instances of the type. With this information, the store is able to detect access patterns that can be optimized to directly operate over the storage representation without hydration (deserialization) the object.
摘要:
A new persistence format for storing objects of a user defined type in a database store enables information about the structure of the type to be communicated to the store. This information enables a number of store optimizations, including direct structural access to members of the type. Specifically, metadata is exchanged between the type implementer and the data store. The store uses the metadata to determine the storage layout for instances of the type. With this information, the store is able to detect access patterns that can be optimized to directly operate over the storage representation without hydration (deserialization) the object.
摘要:
A database system and method allows a user to write program code in a high-level programming language that implements a class that defines the structure of a user-defined type and methods that can be invoked on instances of the type. The class is then registered with the database system, which enforces a specific contract for user-defined types against the class. The contract comprises the following requirements. First, the class must specify one of a plurality of different formats for persisting instances of the user-defined type in a database store. Second, the class must be capable of returning a null value for the user-defined type. Third, the class must provide a method for converting the user-defined type to another type. Once these requirements are satisfied, the database system enables instances of the user-defined type to be created. A user-defined type can be used in all contexts where any other built-in type can be used. This includes defining columns of tables, declaring variables and parameters to functions and stored procedures, and evaluating expressions of the user-defined type in SQL queries and updates. Preferably, the database system stores metadata about the user-defined type for subsequent use in creating instances of the type.
摘要:
A database system and method allows a user to write program code in a high-level programming language that implements a class that defines the structure of a user-defined type and methods that can be invoked on instances of the type. The class is then registered with the database system, which enforces a specific contract for user-defined types against the class. The contract comprises the following requirements. First, the class must specify one of a plurality of different formats for persisting instances of the user-defined type in a database store. Second, the class must be capable of returning a null value for the user-defined type. Third, the class must provide a method for converting the user-defined type to another type. Once these requirements are satisfied, the database system enables instances of the user-defined type to be created. A user-defined type can be used in all contexts where any other built-in type can be used. This includes defining columns of tables, declaring variables and parameters to functions and stored procedures, and evaluating expressions of the user-defined type in SQL queries and updates. Preferably, the database system stores metadata about the user-defined type for subsequent use in creating instances of the type.
摘要:
A database system and method allows a user to write program code in a high-level programming language that implements a class that defines the structure of a user-defined type and methods that can be invoked on instances of the type. The class is then registered with the database system, which enforces a specific contract for user-defined types against the class. The contract comprises the following requirements. First, the class must specify one of a plurality of different formats for persisting instances of the user-defined type in a database store. Second, the class must be capable of returning a null value for the user-defined type. Third, the class must provide a method for converting the user-defined type to another type. Once these requirements are satisfied, the database system enables instances of the user-defined type to be created. A user-defined type can be used in all contexts where any other built-in type can be used. This includes defining columns of tables, declaring variables and parameters to functions and stored procedures, and evaluating expressions of the user-defined type in SQL queries and updates. Preferably, the database system stores metadata about the user-defined type for subsequent use in creating instances of the type.
摘要:
A database system and method allows a user to write program code in a high-level programming language that implements a class that defines the structure of a user-defined aggregate and methods that can be invoked on instances of the user-defined aggregate. The class is then registered with the database system, which enforces a specific contract for user-defined aggregates against the class. The contract comprises the following requirements. First, the class must specify one of a plurality of different formats for persisting instances of the user-defined aggregate in a database store. Second, the class must comprise a first method that can be invoked to initialize the computation of an instance of the user-defined aggregate, a second method that can be invoked to accumulate a plurality of values to be aggregated with the user-defined aggregate, a third method that can be invoked to merge an instance of the user-defined aggregate with another partial aggregation, and a fourth method that can be invoked to compute a final result of an instance of the user-defined aggregate. Once these requirements are satisfied, the database system enables instances of the user-defined aggregate to be created. Preferably, the database system stores metadata about the user-defined aggregate for subsequent use in creating instances of the aggregate.
摘要:
A system and method are provided for modeling structured, semi-structured, and unstructured data all within a single instance of a user defined type (UDT) within a database store. In particular, the XML data model is extended to fields of a UDT. As a result, the properties of the XML data model—such as document order and document structure—can be preserved within instances of a UDT. Moreover, code representing object behavior (i.e., methods that can be invoked on an object in managed code) can be added to the UDT to operate on an XML field, as well as non-XML fields of the UDT. This enables a framework for adding business logic to XML data. The content model of the XML data can be optionally described using XML schema documents associated with the XML fields of the UDT.