Abstract: The present invention extends to methods, systems, and computer program products for optimizing parallel queries using interesting distributions. For each logical operator in an SQL server MEMO, in a top down manner from a root operator to the leaf operators, interesting distributions for the operators can be identified based on the properties of the operators. Identified interesting distributions can be propagated down to lower operators by annotating the lower operators with the interesting distributions. Thus, a SQL server MEMO can be annotated with interesting distributions propagated top down from root to leaf logical operators to generate an annotated SQL server MEMO. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator. Annotated interesting properties can be used to prune operators, thereby facilitating a more tractable search space for a parallel query plan.

Abstract: The present invention extends to methods, systems, and computer program products for optimizing parallel queries using interesting distributions. For each logical operator in an SQL server MEMO, in a top down manner from a root operator to the leaf operators, interesting distributions for the operators can be identified based on the properties of the operators. Identified interesting distributions can be propagated down to lower operators by annotating the lower operators with the interesting distributions. Thus, a SQL server MEMO can be annotated with interesting distributions propagated top down from root to leaf logical operators to generate an annotated SQL server MEMO. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator. Annotated interesting properties can be used to prune operators, thereby facilitating a more tractable search space for a parallel query plan.

Abstract: The present invention extends to methods, systems, and computer program products for optimizing parallel queries using interesting distributions. For each logical operator in an SQL server MEMO, in a top down manner from a root operator to the leaf operators, interesting distributions for the operators can be identified based on the properties of the operators. Identified interesting distributions can be propagated down to lower operators by annotating the lower operators with the interesting distributions. Thus, a SQL server MEMO can be annotated with interesting distributions propagated top down from root to leaf logical operators to generate an annotated SQL server MEMO. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator. Annotated interesting properties can be used to prune operators, thereby facilitating a more tractable search space for a parallel query plan.

Abstract: A query can be executed over incomplete data and produce a partial result. Moreover, the partial result or portion thereof can be classified in accordance with a partial result taxonomy. In accordance with one aspect, the taxonomy can be defined in terms of data correctness and cardinality properties. Further, partial result analysis can be performed at various degrees of granularity. Classified partial result can be presented on a display device to allow user to view and optionally interact with the partial result.

Abstract: A single system image is provided for a parallel data warehouse system by exposing a shell database within a database management system comprising metadata and statistics regarding externally stored data. Further, functionality of the database management system can be exploited to perform pre-execution tasks. In one instance, one or more execution plans can be generated by the database management system for an input command and subsequently employed to generate a distributed execution plan.

Abstract: The present invention extends to methods, systems, and computer program products for optimizing parallel queries using interesting distributions. For each logical operator in an SQL server MEMO, in a top down manner from a root operator to the leaf operators, interesting distributions for the operators can be identified based on the properties of the operators. Identified interesting distributions can be propagated down to lower operators by annotating the lower operators with the interesting distributions. Thus, a SQL server MEMO can be annotated with interesting distributions propagated top down from root to leaf logical operators to generate an annotated SQL server MEMO. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator. Annotated interesting properties can be used to prune operators, thereby facilitating a more tractable search space for a parallel query plan.

Abstract: A single system image is provided for a parallel data warehouse system by exposing a shell database within a database management system comprising metadata and statistics regarding externally stored data. Further, functionality of the database management system can be exploited to perform pre-execution tasks. In one instance, one or more execution plans can be generated by the database management system for an input command and subsequently employed to generate a distributed execution plan.

Abstract: The present invention extends to methods, systems, and computer program products for optimizing queries of parallel databases. Queries can be partially optimized at an optimizer that is unaware of its use to optimize queries for parallel processing. The optimizer can produce a data structure (e.g., a SQL Server MEMO) that encapsulates a logical serial plan search space. The logical serial plan search space may not incorporate any notion of parallelism into the plan space itself. A parallel-aware optimizer can parallelize the logical serial plan search space by augmenting the data structure (e.g., transforming the SQL Server MEMO into a parallel MEMO). Augmentation can be with data movement operations that move data associated one or more compute nodes in a distributed architecture. Cost estimates can be calculated for the operations contained in the parallelized data structure. The parallel plan with the lowest estimated cost can be selected for the query.

Abstract: The min-repro finding technique described herein is designed to ease and speed-up the task of finding a min-repro, a minimum configuration that reproduces a problem in database-related products. Specifically, in one embodiment, the technique simplifies transformations in order to find one or more min-repros. One embodiment provides a high-level script language to automate some sub-tasks and to guide the search for a simpler the configuration that reproduces the problem. Yet another embodiment provides record-and-replay functionality, and provides an intuitive representation of results and the search space. These tools can save hours of time for both customers and testers to isolate the problem and can result in faster fixes and large cost savings to organizations.