摘要:
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. An integrated query processing pipeline may analyze the query to determine whether a single-item or multiple-item operation is specified in order to select an appropriate query operator, which may improve the efficiency and performance of the data source querying.
摘要:
Systems and methods for extension of a query language for defining a simple formulation of joins by capturing the semantics of an existing linkage between a plurality of tables, via employing a reference join. Such reference join enables a compiler to exploit existing relationships in a data base, and employ existing knowledge about referential constraints for an unambiguous transformation of the reference join expression into the equivalent INNER JOIN on the columns involved. Accordingly, a simpler query syntax and semantics can be provided to express multi-table join navigation over primary key/foreign key relations, for example.
摘要:
A system and method for creation, modification and/or use of plan guide(s) is provided. Plan guide(s) can be employed to optimize the performance of query(ies) when it is not possible and/or desirable to change the text of the query directly. Plan guides can be useful, for example, when a small subset of queries in a database application deployed from a third-party vendor is not performing as expected. Plan guides influence optimization of queries by attaching query hints to them. In accordance with an aspect of the subject invention, a query plan execution system is provided. The system includes an execution component, a query optimizer, and, a plan cache. Plan guides and other associated metadata are stored in a plan guide metadata store.
摘要:
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. An integrated query processing pipeline may analyze the query to determine whether a single-item or multiple-item operation is specified in order to select an appropriate query operator, which may improve the efficiency and performance of the data source querying.
摘要:
A compositional application programming interface (API) permits non-sequential construct declaration independent of other API calls. A wrapper is applied to an imperative API to provide a compositional interface that enables arbitrary and autonomous construct declaration. Additionally, a literal syntax (e.g., code literals, graphic literals . . . ) affords a convenient declaration mechanism for such constructs.
摘要:
The subject disclosure pertains to systems and methods for dynamic parsing. A dynamic parser can perform syntactic analysis or parsing of input data consisting of a set of tokens based upon a provided grammar including conditional tokens. While the parser grammar can be fixed, the dynamic parser can utilize an independent transform function at parse time to translate or replace particular tokens, effectively performing dynamic parsing. The transform function can be utilized in conjunction with conditional tokens to selectively activate and deactivate particular grammar rules. Additionally, systems and methods for automatically generating a dynamic parser from a grammar description are described herein.
摘要:
The SQL Algebrizer of the present invention comprises a plurality of algorithms to “algebrize” SQL Trees to QP Algebra using an approach that is more consistent and much more efficient than typical algebrizers. More specifically, the Algebrizer of the present invention processes a SQL Tree using a reduced number of recursive depth-first passes by performing multiple operations in a single pass. Furthermore, the Algebrizer of the present invention also performs the operation of constant folding in this single, multi-operation pass so that the QP, upon receiving the QP Algebra, needs not perform this operation at all.
摘要:
A compositional application programming interface (API) permits non-sequential construct declaration independent of other API calls. A wrapper is applied to an imperative API to provide a compositional interface that enables arbitrary and autonomous construct declaration. Additionally, a literal syntax (e.g., code literals, graphic literals . . . ) affords a convenient declaration mechanism for such constructs.
摘要:
The subject disclosure pertains to systems and methods for dynamic parsing. A dynamic parser can perform syntactic analysis or parsing of input data consisting of a set of tokens based upon a provided grammar including conditional tokens. While the parser grammar can be fixed, the dynamic parser can utilize an independent transform function at parse time to translate or replace particular tokens, effectively performing dynamic parsing. The transform function can be utilized in conjunction with conditional tokens to selectively activate and deactivate particular grammar rules. Additionally, systems and methods for automatically generating a dynamic parser from a grammar description are described herein.
摘要:
A query language system is provided that includes a query component that specifies operations for one or more items in a data set. An aggregator component identifies one or more keys associated with the data set, the keys are supplied to one or more aggregators that perform direct computations from the keys in order to determine at least one aggregated value for the data set.