Abstract: A method and a system for mapping a flattened data structure into a relation preserving data structure is disclosed. The method includes receiving a flattened schema comprising a plurality of columns. The method includes receiving a plurality of user inputs from a user. The plurality of user inputs comprises a plurality of identifiers. The method includes defining a sample target hierarchical schema based on user inputs. The method includes preparing a nested hierarchical structure corresponding to the sample target hierarchical schema in a User Interface (UI) representation. The nested hierarchical structure comprises a plurality of nodes with corresponding identifiers and relationships of the plurality of nodes. The method includes performing an Artificial Intelligence (AI) based mapping of columns of the flattened schema to respective nodes of the plurality of nodes of the nested hierarchical structure. The method further includes generating a target hierarchical schema based on AI based mapping.

Abstract: A method and a system for mapping a flattened data structure into a relation preserving data structure is disclosed. The method includes receiving a flattened schema comprising a plurality of columns. The method includes receiving a plurality of user inputs from a user. The plurality of user inputs comprises a plurality of identifiers. The method includes defining a sample target hierarchical schema based on user inputs. The method includes preparing a nested hierarchical structure corresponding to the sample target hierarchical schema in a User Interface (UI) representation. The nested hierarchical structure comprises a plurality of nodes with corresponding identifiers and relationships of the plurality of nodes. The method includes performing an Artificial Intelligence (AI) based mapping of columns of the flattened schema to respective nodes of the plurality of nodes of the nested hierarchical structure. The method further includes generating a target hierarchical schema based on AI based mapping.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for streaming external data in parallel from a second distributed system to a first distributed system. One of the methods includes receiving a query that requests a join of first rows of a first table in a first distributed system with second rows of an external table, the external table representing data in a second distributed system. Each of the segment nodes communicates with a respective extension service that obtains fragments from one or more data nodes of the second distributed system according to location information for the respective fragments, and provides to the segment node a stream of data corresponding to second rows of the external table. Each of the segment nodes computes joined rows between the first rows of the first table and the stream of data corresponding to second rows of the external table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for streaming external data in parallel from a second distributed system to a first distributed system. One of the methods includes receiving a query that requests a join of first rows of a first table in a first distributed system with second rows of an external table, the external table representing data in a second distributed system. Each of the segment nodes communicates with a respective extension service that obtains fragments from one or more data nodes of the second distributed system according to location information for the respective fragments, and provides to the segment node a stream of data corresponding to second rows of the external table. Each of the segment nodes computes joined rows between the first rows of the first table and the stream of data corresponding to second rows of the external table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for streaming external data in parallel from a second distributed system to a first distributed system. One of the methods includes receiving a query that requests a join of first rows of a first table in a first distributed system with second rows of an external table, the external table representing data in a second distributed system. Each of the segment nodes communicates with a respective extension service that obtains fragments from one or more data nodes of the second distributed system according to location information for the respective fragments, and provides to the segment node a stream of data corresponding to second rows of the external table. Each of the segment nodes computes joined rows between the first rows of the first table and the stream of data corresponding to second rows of the external table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for streaming external data in parallel from a second distributed system to a first distributed system. One of the methods includes receiving a query that requests a join of first rows of a first table in a first distributed system with second rows of an external table, the external table representing data in a second distributed system. Each of the segment nodes communicates with a respective extension service that obtains fragments from one or more data nodes of the second distributed system according to location information for the respective fragments, and provides to the segment node a stream of data corresponding to second rows of the external table. Each of the segment nodes computes joined rows between the first rows of the first table and the stream of data corresponding to second rows of the external table.

Abstract: Coarse-grained system-wide database privileges are transformed into new finer-grained database object privileges that are user-centric and specific to particular objects by creating an object class defining certain generic operations on objects, and defining within the object class a new object that embodies permissible actions on a particular database object. The new object is stored in a catalog table that comprises an object privilege table and is associated in the object privilege table with a consolidated grouping of object privileges of users relative to the new object.

Abstract: A computer readable storage medium includes executable instructions to store load data in new rows of an append only table within a data warehouse, without updating or deleting existing rows in the append only table. The new rows are added in a database transaction that guarantees that the distributed reads and writes of all transactions are processed reliably and that the transactions obey snapshot isolation rules. Data changes associated with the load data are maintained in a separate update table. Data from the append only table is merged with data changes from the update table to supply read data.

Abstract: A method, article of manufacture, and apparatus for recovering databases. In some embodiments, this includes switching an active segment to a resynchronization mode, receiving a change tracking log, determining a data block based on the change tracking log, and resynchronizing the determined data block with a non-active segment. In some embodiments, writes performed on the active segment are synchronized with the non-active segment.

Abstract: A computer readable storage medium includes executable instructions to store load data in new rows of an append only table within a data warehouse, without updating or deleting existing rows in the append only table. The new rows are added in a database transaction that guarantees that the distributed reads and writes of all transactions are processed reliably and that the transactions obey snapshot isolation rules. Data changes associated with the load data are maintained in a separate update table. Data from the append only table is merged with data changes from the update table to supply read data.

Abstract: Formatting data is disclosed. An indication of a specified data to be formatted between a format of a database and a format external to database is received. A formatter of the database is used to format the specified data between the format of the database and the format external to the database. The formatter has been integrated with the database using a formatter code defined external to the database.

Abstract: A method, article of manufacture, and apparatus for recovering databases. In some embodiments, this includes switching an active segment to change tracking mode, intercepting write related changes on the active segment while in the change tracking mode, populating a change tracking log based on the intercepted write related changes, and storing the populated change tracking log in a storage device. In some embodiments, the storage device is memory. In some embodiments, the change tracking log if flushed from memory to disk.

Abstract: A computer readable storage medium includes executable instructions to store load data in new rows of an append only table within a data warehouse, without updating or deleting existing rows in the append only table. The new rows are added in a database transaction that guarantees that the distributed reads and writes of all transactions are processed reliably and that the transactions obey snapshot isolation rules. Data changes associated with the load data are maintained in a separate update table. Data from the append only table is merged with data changes from the update table to supply read data.

Abstract: A computer readable storage medium includes executable instructions to store load data in new rows of an append only table within a data warehouse, without updating or deleting existing rows in the append only table. The new rows are added in a database transaction that guarantees that the distributed reads and writes of all transactions are processed reliably and that the transactions obey snapshot isolation rules. Data changes associated with the load data are maintained in a separate update table. Data from the append only table is merged with data changes from the update table to supply read data.