Abstract: As an abstract representation, a set of equivalent logical structures representative of multiple execution plans for execution of a database query can be used to optimize a database query. A logical structure can include one or more logical operators each representing multiple physical operators for executing the database query. Group and Operator Rules can be applied as rules to the set of equivalent logical structures to obtain additional equivalent logical structures and logical operator until no additional logical operators can be obtained. A set of possible implementation plans for the total number of the obtained logical operators can be obtained, for example, based on physical and/or implementation context.

Abstract: A database system receives a request from a user. The request invokes a data set function (DSF) and uses a property to be provided by the DSF. The database system determines that a function descriptor is available for the DSF. The function descriptor is expressed as markup language instructions. The function descriptor defines the property of the DSF. The database system uses the function descriptor to define a property for the DSF.

Abstract: Execution of a query invoking an analytical function (AF) is optimized. The query includes a join operation between an AF table and an AuxiliaryTable and includes determining that the AF includes a plurality of AF properties. Query-level properties about the query are inferred. It is determined to change an order of the join operation from the plurality of AF properties and query-level properties.

Abstract: As an abstract representation, a set of equivalent logical structures representative of multiple execution plans for execution of a database query can be used to optimize a database query. A logical structure can include one or more logical operators each representing multiple physical operators for executing the database query. Group and Operator Rules can be applied as rules to the set of equivalent logical structures to obtain additional equivalent logical structures and logical operator until no additional logical operators can be obtained. A set of possible implementation plans for the total number of the obtained logical operators can be obtained, for example, based on physical and/or implementation context.

Abstract: The execution of the one or more database queries can be optimized by using a multi-platform cost model that take into account the respective cost of execution in each one of the multiple execution platforms. The respective costs of the execution can, for example, include cost associated with one or more operators for executing the one or more database queries in each one of the multiple execution platforms and/or the costs of exchanging data between the multiple execution platforms.

Abstract: As an abstract representation, a set of equivalent logical structures representative of multiple execution plans for execution of a database query can be used to optimize a database query. A logical structure can include one or more logical operators each representing multiple physical operators for executing the database query. Group and Operator Rules can be applied as rules to the set of equivalent logical structures to obtain additional equivalent logical structures and logical operator until no additional logical operators can be obtained. A set of possible implementation plans for the total number of the obtained logical operators can be obtained, for example, based on physical and/or implementation context.