摘要:
Systems and methods that employ auxiliary data structures in form of indexes (e.g., slice indexes) to process incoming queries in query retrieval systems (e.g., Online Analytical Processing (OLAP) environments.) The indexing component analyzes attributes involved in predicate conditions of filter requests to form slice indexes for same filtering criteria, wherein resulting data set share the same filtering criteria in form of attributes. The indexes of the subject innovation can be created on-the-fly, and typically without intervention by system administrators.
摘要:
Systems and methods that employ auxiliary data structures in form of indexes (e.g., slice indexes) to process incoming queries in query retrieval systems (e.g., Online Analytical Processing (OLAP) environments.) The indexing component analyzes attributes involved in predicate conditions of filter requests to form slice indexes for same filtering criteria, wherein resulting data set share the same filtering criteria in form of attributes. The indexes of the subject innovation can be created on-the-fly, and typically without intervention by system administrators.
摘要:
A relationship amongst multiple relationships between database tables can be specified independent of a query. More specifically, a function (USERELATIONSHIP) can be introduced to the DAX language (Data Analysis Expressions), which provides a way to author formulas that are not evaluated immediately, but that can be evaluated dynamically and concurrently in many different contexts. The function enables a single relationship to be specified in the calculation formula away from the query. This provides a mechanism within the formula that specifies specific relationship(s) that are to be followed when the dynamic expression is evaluated.
摘要:
A system and method for facilitating querying one or more data sources. A system provides mechanisms to enable flexible specification of user queries and generation of one or more SQL queries that correspond closely to corresponding user queries. An operator tree and a logical operator tree may be created as intermediate steps to generate the one or more SQL queries. Capabilities of data sources are determined and used to generate remotable SQL queries for composable queries, to reduce an amount of post-processing that is performed on result sets. The system enables user queries that extend beyond those defined by a data model.
摘要:
The subject disclosure relates to querying of column based data encoded structures enabling efficient query processing over large scale data storage, and more specifically with respect to complex queries implicating filter and/or sort operations for data over a defined window. In this regard, in various embodiments, a method is provided that avoids scenarios involving expensive sorting of a high percentage of, or all, rows, either by not sorting any rows at all, or by sorting only a very small number of rows consistent with or smaller than a number of rows associated with the size of the requested window over the data. In one embodiment, this is achieved by splitting an external query request into two different internal sub-requests, a first one that computes statistics about distribution of rows for any specified WHERE clauses and ORDER BY columns, and a second one that selects only the rows that match the window based on the statistics.
摘要:
A data model for accessing data in a relational database in an OLAP system utilizes a multiple-hierarchy dimension. The dimension includes a set of attributes. Each attribute is bound to a column in the relational database. A logical structure is defined, indicating the relationships between the attributes. Hierarchies are defined. Each hierarchy includes a sequence of attributes. A hierarchy provides a common drill-down path that a database user can utilize to access the database. A hierarchy can include a single attribute or a combination of attributes. Both the relationships between the attributes and the sequence of attributes in a hierarchy are defined independent of any restrictions associated with the database.
摘要:
A method is described herein for causing an analytical database server to store query results in a memory. In the method, a first header element and a request to query an analytical database is received. The first header element indicates that a query result should be stored. The analytical database is queried according to the request, and the query result is stored. An identifier associated with the query result and a second header element corresponding to the identifier is then transmitted.
摘要:
The subject invention pertains to the integration of an object model and a multidimensional database query language such as MDX. In particular, multidimensional declarative query language entities can be exposed through objects in an object model. The object model enables generation and employment of procedural language functions, routines, or procedures that interact with multidimensional database data. This effectively provides an extension for multidimensional query languages. For example, procedures can be stored and invoked from a declarative language query. Furthermore, the object model disclosed herein can expose a context object to enable conditional procedures based on the context of execution.
摘要:
A system that facilitates analyzing content of a multi-dimensional structure comprises a calculation component that receives statements in a declarative language relating to one or more of an assignment and calculation and executes such statements against a multi-dimensional structure. A pass generation component creates a pass in order to maintain content of the multi-dimensional structure as it existed prior to execution of the statement, the pass is accessible upon reference to such pass.
摘要:
The subject invention pertains to systems and methods that facilitate development and debugging of calculations in a multidimensional data environment or model. Data cube calculation scripts, including those provided in MDX (Multidimensional Expressions), can be executed or applied incrementally. Breakpoints can be set with respect to a calculation script and the cube state can be viewed and queried via a user interface. Users are enabled by the subject systems and methods to step through calculation scripts, identify the effects on a cube, and alter the script if the desired results failed to occur. In addition to debugging, the systems and methods can be employed for initial development of scripts.