Abstract: Architecture that extends existing types including constructed and sealed types using extension methods. Extension methods are static methods that can be invoked using instance method syntax. Extension methods are declared by specifying the keyword “this” as a modifier on the first parameter of the methods. Extension methods have all the capabilities of regular static methods. In addition, once imported, extension methods can be invoked using instance method syntax. Also disclosed are rules for importing extension methods, and extension method invocations. Extension methods are imported through using-namespace-directives. In addition to importing the types contained in a namespace, a using-namespace-directive imports all extension methods in all static classes in the namespace. In effect, imported extension methods appear as additional methods on the types that are given by their first parameter and have lower precedence than regular instance methods.

Abstract: Anonymous types for a programming language. Non-denotable anonymous types are types that a compiler generates on behalf of a programmer and can then be used as nominal types. Insofar as anonymous types do not have a name, they can be used only inside a method in which they are created. Additionally, an anonymous type cannot be exposed in any way outside of the method. Syntax to create an anonymous type is useful when employed with a Select operator to generate a result with a particular shape, without the need of having a regular type for it. Anonymous types are expressible such that an expression of that type can be written. Translation of an anonymous type by a compiler generates a nominal class that implements Equals and GetHashCode methods. There is equivalence of anonymous types within the same method, and conversion of an unrealized structural type into structurally compatible nominal type.

Abstract: A system and method for parsing XML is provided. The method includes associating an input stream with a pull model parser, accepting requests to selectively parse out XML items from the input stream and retrieving metadata information associated with the parsed out XML items. The method further includes checking the pulled XML item to determine whether it conforms to XML syntax and/or semantic standards and validating the pulled XML item to determine whether it conforms to a selected DTD.

Abstract: A unique formatting scheme for object-relational mapping allows disparate applications that adopt the scheme to seamlessly access data in disparate relational databases. The formatting scheme contemplates a common format that conveys the mapping information through (i) attributes embedded with code objects, and (ii) an external mapping source. Adoption of the common format can result in several advantages for network-based client-server operations: (i) Software developers can continue programming in their existing languages. (ii) Data servers from various vendors can also continue to be developed and managed in the vendors' core programming languages. (iii) Vendors that employ client applications which have adopted the common format can consistently use various data warehouses without incurring customization costs.

Abstract: Systems and methods that enable consistent navigation (for a database and memory environment) in object relational mapping. This typically ensures fidelity of object graph via restrictions on collections of persistent objects (e.g., entity sets, entity refs . . . ). Moreover, a tracking component can detect changes as they occur, and only a copy of the objects that have changed can be created, to optimize operation.

Abstract: A program execution engine that facilitates generic type variance verification is provided. The execution engine receives a program executable in the form of intermediate language (IL). The program executable can be based on code that includes expression(s) with generic type(s) which have been identified as requiring variance verification (e.g., covariance and/or contra-variance). The execution engine includes a variance verification component that dynamically determines whether value(s) associated with the generic type(s) identified as requiring variance verification comply with the particular variance verification requirement. The variance verification component can provide error information (e.g., throw an exception), if the specified variance is not safely compliant. Variance verification can be based on static checking which places the burden on a source language compiler to emit the run-time checks in intermediate language (IL), if run-time checked variance is required.

Abstract: Architecture that extends existing types including constructed and sealed types using extension methods. Extension methods are static methods that can be invoked using instance method syntax. Extension methods are declared by specifying the keyword “this” as a modifier on the first parameter of the methods. Extension methods have all the capabilities of regular static methods. In addition, once imported, extension methods can be invoked using instance method syntax. Also disclosed are rules for importing extension methods, and extension method invocations. Extension methods are imported through using-namespace-directives. In addition to importing the types contained in a namespace, a using-namespace-directive imports all extension methods in all static classes in the namespace. In effect, imported extension methods appear as additional methods on the types that are given by their first parameter and have lower precedence than regular instance methods.

Abstract: The subject disclosure pertains to systems and methods that facilitate retrieval of data. In particular, an application defined data shape can regulate loading of data for use in an object relational mapping system, enabling the object-oriented application to access data in a relational data base system. Data shapes define policies that control data retrieval, enabling efficient data loading. A data shape allows users to declaratively specify a set of policies to be applied to all queries associated with the data shape. In particular, data shapes can include policies that control eager loading. In addition, data shapes can also include filtering policies intended to reduce or limit data retrieved from a relational database.

Abstract: The subject invention relates to systems and methods that provide null capabilities within the context of programming languages. In one aspect, a system is provided that facilitates null-support in various programming languages. The system includes one or more types associated with at least one programming language. A type modifier is provided to signal that the type is nullable. The type modifier enables a multi-element structure to be automatically created in association with the type wherein, the multi-element structure includes the type and a Boolean element indicating whether or not the variable is null.

Abstract: An operation (such as a relational query) may be processed on a processing engine (such as a relational database server) on behalf of a client. A conventional processing involves the delivery of the operation to the processing engine, which executes the entire operation to completion and returns a result data set. It may be more efficient to allocate part of the operation to be performed on the client, but a developer may be unable or unavailable to rewrite the operation in a distributed manner. Instead, the operation may be automatically partitioned into a pre-engine client portion, a processing engine portion, and a client portion, and the instructions of each portion may be automatically allocated respectively to the client, the server, and the client. The partitioning may be adjusted to conserve computing resources, such as bandwidth and storage, and the instructions may be reordered to improve the processing of the operation.

Abstract: Expression tree versatility and applicability are enhanced to facilitate programming across various program languages and execution contexts. An expression tree can represent programmatic code as data in a representation common to multiple process mechanisms. As a result, entire programs or portions thereof can be captured and processed by a numerous common language components. Further, language specific concepts can be reduced to the common representation to enable language independent employment.

Abstract: The utilization of data services (such as web services) may involve the invocation of services, which may reduce performance and overburden the server. In some scenarios, the invocation may be specified in a language that does not support batch invocation, but it may not be feasible to re-code the invocations in a language that supports batching. Instead, the service invocations may be automatically translated into a batch logic specified in a batch-capable language and sent to the service as a batch. For example, a local proxy may receive a language-integrated query having two or more service invocations, compile the query into an expression tree including the two or more invocations, and send the expression tree to the service host to achieve the batch processing of the service invocations.

Abstract: Queries targeting various data sources are processed in a query processing pipeline that parses the query into a set of operations (e.g., an expression tree or a translated SQL query) using a set of query operators, each handling a particular type of operation. The query operators are often designed in an unspecialized manner, such that each query operator handles one query operation in an atomic, generic manner (e.g., sorting generic data items for an ORDER BY clause.) More efficient queries may be devised by including specialized queries that operate in common but special cases, such as a sorting of a particular data type (e.g., a floating-point number sort) or a sequence of two or more operations that are often performed together (e.g., a WHERE test of an attribute followed by a SELECT of the same attribute.) The use of specialized operators may result in the formulation of more efficient queries.

Abstract: Queries against data sources (such as language-integrated queries to be applied against relational databases) may be prepared for processing by a query processing pipeline. This pipeline performs services including transforming the query into a form more easily applied by the data source, e.g., into SQL, by matching query terms with query operators configured to handle various query operations. Many query processing pipelines include single-item query operators that perform individual operations (e.g., an updating query operator that specifies an updating of individual records of a table.) An integrated query pipeline may be devised that includes both single-item query operators and multiple-item query operators that specify operations on sets of data items.

Abstract: Data source queries may be specified in various languages, such as SQL, XQuery, and object-oriented languages, and each language may have various linguistic features that enable different types of queries. It may be advantageous to formulate mixed language queries having portions specified in a first language and portions specified in a second language, and to provide mixed language query evaluation components that can parse portions of queries of different languages. It may also be advantageous to permit the translation of single language queries into multiple languages to be parsed by such mixed language query evaluation components. Such techniques may permit queries to utilize linguistic features and processing techniques of one language that are less efficient, less direct, or simply unavailable in another language.

Abstract: The subject disclosure pertains to code generation patterns for use in object relational mapping. The code patterns may be used to manage bidirectional relationships and ensure consistency. The code patterns may support on-demand or deferred loading of relational data. Change detection and tracking are also provided. In addition, a default member modifier allows developers to override tool generated source code without directly modifying the generated source code.

Abstract: The subject disclosure pertains to systems and methods for supporting null capabilities for general purpose programming languages. Low level, runtime support for a nullable type is provided to ensure consistency and coherency. An execution component restricts support of the nullable type to programming language types that lack a null capability. The execution component may also provide support for conversion between the nullable type and a reference type.

Abstract: A system and method for employing a programming language based on structural types on top of a nominal type runtime environment is disclosed. The system utilizes adapters and coercive subtyping to achieve precise typing while preserving aliasing. Furthermore, the system employs a universal value representation to achieve cross-assembly type equivalence.

Abstract: A unique formatting scheme for object-relational mapping allows disparate applications that adopt the scheme to seamlessly access data in disparate relational databases. The formatting scheme contemplates a common format that conveys the mapping information through (i) attributes embedded with code objects, and (ii) an external mapping source. Adoption of the common format can result in several advantages for network-based client-server operations: (i) Software developers can continue programming in their existing languages. (ii) Data servers from various vendors can also continue to be developed and managed in the vendors' core programming languages. (iii) Vendors that employ client applications which have adopted the common format can consistently use various data warehouses without incurring customization costs.

Abstract: Providing for read/write access to captured free variables expressed as environment data objects is disclosed herein. By way of example, free variables can be rewritten as a field of a private class, and accessed via an instance of the private class captured within the environment data object. In such a manner, no need of a placeholder or proxy function is required to access the free variable. Consequently, the subject innovation provides a simplified method for capturing free variables within expression trees and providing read/write access to such variables.