Abstract: Provided are a computer program product, system, and method for generating sub-indexes from an index to compress the index. An index has levels of nodes for a composite key comprised of component keys. Each node includes at least one composite key value comprised of component key values. A plurality of sub-indexes is generated including one sub-index for each component key of the composite key. Nodes are generated in each sub-index corresponding to nodes in the index. In each node of the nodes of the sub-index, a component key value is generated, for the component key for which the sub-index was generated, from at least one composite key value in the corresponding node of the index. The sub-indexes are used to search for a record matching a search composite key value in the database using component key values of the search composite key value.

Abstract: Using historical queries to determine database columns to populate a partial database. A partial database is created based, at least in part, on key values related to columns in a database for which the columns are most frequently accessed.

Abstract: Provided are a computer program product, system, and method for generating sub-indexes from an index to compress the index. An index has levels of nodes for a composite key comprised of component keys. Each node includes at least one composite key value comprised of component key values. A plurality of sub-indexes is generated including one sub-index for each component key of the composite key. Nodes are generated in each sub-index corresponding to nodes in the index. In each node of the nodes of the sub-index, a component key value is generated, for the component key for which the sub-index was generated, from at least one composite key value in the corresponding node of the index. The sub-indexes are used to search for a record matching a search composite key value in the database using component key values of the search composite key value.

Abstract: A method to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A method for dynamically updating database statistics and a plurality of access paths associated with at least one database table is provided. The method may include identifying at least one dynamically changing column associated with the at least one database table. The method may further include determining at least one predicate pattern associated with the identified at least one dynamically changing column. Additionally, the method may include dynamically detecting at least one range change associated with the determined at least one predicate pattern based on at least one record insert. The method may also include updating the plurality of database statistics associated with the identified at least one dynamically changing column based on the dynamically detected at least one range change. The method may further include determining at least one filter factor based on the updated plurality of database statistics associated with the identified at least one dynamically changing column.

Abstract: A method for dynamically updating database statistics and a plurality of access paths associated with at least one database table is provided. The method may include identifying at least one dynamically changing column associated with the at least one database table. The method may further include determining at least one predicate pattern associated with the identified at least one dynamically changing column. Additionally, the method may include dynamically detecting at least one range change associated with the determined at least one predicate pattern based on at least one record insert. The method may also include updating the plurality of database statistics associated with the identified at least one dynamically changing column based on the dynamically detected at least one range change. The method may further include determining at least one filter factor based on the updated plurality of database statistics associated with the identified at least one dynamically changing column.

Abstract: A computer system to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A method for dynamically updating database statistics and a plurality of access paths associated with at least one database table is provided. The method may include identifying at least one dynamically changing column associated with the at least one database table. The method may further include determining at least one predicate pattern associated with the identified at least one dynamically changing column. Additionally, the method may include dynamically detecting at least one range change associated with the determined at least one predicate pattern based on at least one record insert. The method may also include updating the plurality of database statistics associated with the identified at least one dynamically changing column based on the dynamically detected at least one range change. The method may further include determining at least one filter factor based on the updated plurality of database statistics associated with the identified at least one dynamically changing column.

Abstract: A method for dynamically updating database statistics and a plurality of access paths associated with at least one database table is provided. The method may include identifying at least one dynamically changing column associated with the at least one database table. The method may further include determining at least one predicate pattern associated with the identified at least one dynamically changing column. Additionally, the method may include dynamically detecting at least one range change associated with the determined at least one predicate pattern based on at least one record insert. The method may also include updating the plurality of database statistics associated with the identified at least one dynamically changing column based on the dynamically detected at least one range change. The method may further include determining at least one filter factor based on the updated plurality of database statistics associated with the identified at least one dynamically changing column.

Abstract: Using historical queries to determine database columns to populate a partial database. A partial database is created based, at least in part, on key values related to columns in a database for which the columns are most frequently accessed.

Abstract: A computer program product to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A computer program product to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A method to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A computer program product to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: A method to optimize a database is provided. A processor determines a frequency of search for a plurality of columns in a table. A processor determines a length of the plurality of columns. A processor determines a rank for the plurality of columns based, at least in part, on both the frequency of search and the length of the plurality of columns. A processor generates a first set of combinations of the plurality of columns. A processor determines an optimization of the first set of combinations of the plurality of columns. A processor selects an optimal combination of the first set of combinations, wherein the optimization of the optimal combination is greater than the optimization for all other combinations in the first set of combinations. A processor moves the plurality of columns excluded from the optimal combination.

Abstract: The invention provides for verifying correctness of a database system. A SQL instruction is received and access paths of the received SQL instruction are extended. The SQL instruction is executed by using the extended access paths, and the correctness of the database system is verified according to results of executing the SQL instruction. With the method and system of the invention, the object of verifying correctness of a database system by automatically extending access paths of SQL statement may be achieved, and the object of verifying correctness of a database system scientifically, effectively and purposefully based on ratio of error or defect present in database itself due to various data manipulation approaches (different values of access path elements) may also be achieved.

Abstract: Embodiments relate to a system, computer program product and method for database query optimization. An aspect includes a method that extracts complex predicates from a query statement, the query statement having at least two complex predicates. The method then executes a query associated with the query statement and obtains at least a respective execution structure cost (?Ti) for each of the complex predicates. The method also calculates an overall execution structure cost corresponding to each of the complex predicates, the complex predicates being arranged according to result of the query and the execution structure costs (?Ti); and optimizes a database query by selecting the arrangement of complex predicates having a lowest overall execution structure cost.

Abstract: Disclosed is an energy-saving method for operating a smart doorbell including an activating element which is in a sleeping mode when the activating element is not activated, the activating element includes an electrical doorbell, a photographing module, a communicating module, a first processor, and a second processor, the method comprises: a step of activating the first processor while a movement of an object is sensed by a first sensor; a step of activating the photographing module and the second processor while a second sensor senses that the object is approaching toward the electrical doorbell, analyzing an image information of the object captured by the photographing module; and a step of activating the communicating module while the image information is analyzed that has a human image approaching toward the electrical doorbell, so as to achieve a goal of real time response to a bell call by consuming less energy.

Abstract: Controlling a dump for a database by determining a state of a diagnosis flag associated with the structured query language (SQL) statement in response to a SQL statement being executed for the database. The diagnosis flag is used to indicate if a database dump should be performed. A database dump is performed for the SQL statement in response to determining that the diagnosis flag indicates that a dump is to be performed.