Abstract: A data transformation system includes a schema inference module and an export module. The schema inference module is configured to dynamically create a cumulative schema for objects retrieved from a first data source. Each of the retrieved objects includes (i) data and (ii) metadata describing the data. Dynamically creating the cumulative schema includes, for each object of the retrieved objects, (i) inferring a schema from the object and (ii) selectively updating the cumulative schema to describe the object according to the inferred schema. The export module is configured to output the data of the retrieved objects to a data destination system according to the cumulative schema.

Abstract: A method of operating a data analysis system includes retrieving objects from a data source. Each of the retrieved objects includes (i) data and (ii) metadata describing the data. The method further includes dynamically creating a cumulative schema by, for each object of the retrieved objects: (i) inferring a schema from the object based on the metadata of the object and inferred data types of elements of the data of the object, (ii) creating a unified schema, wherein the unified schema describes both (a) the object described by the inferred schema and (b) a cumulative set of objects described by the cumulative schema, and (iii) storing the unified schema as the cumulative schema. The method further includes exporting the data of each of the retrieved objects to a data warehouse.

Abstract: A method of operating a query system includes retrieving objects from a data source. Each of the retrieved objects includes (i) data and (ii) metadata describing the data. The method further includes dynamically creating a cumulative schema. The dynamically creating includes, for each object of the retrieved objects, (i) inferring a schema from the object based on the metadata of the object and inferred data types of elements of the data of the object, (ii) creating a unified schema, and (iii) storing the unified schema as the cumulative schema. The unified schema describes both (a) the object described by the inferred schema and (b) a cumulative set of objects described by the cumulative schema. The method further includes storing the data of each of the retrieved objects in a storage service.

Abstract: A data transformation system includes a schema inference module and an export module. The schema inference module is configured to dynamically create a cumulative schema for objects retrieved from a first data source. Each of the retrieved objects includes (i) data and (ii) metadata describing the data. Dynamically creating the cumulative schema includes, for each object of the retrieved objects, (i) inferring a schema from the object and (ii) selectively updating the cumulative schema to describe the object according to the inferred schema. The export module is configured to output the data of the retrieved objects to a data destination system according to the cumulative schema.

Abstract: A distributed balanced tree having a plurality of nodes distributed across a plurality of servers is accessed. Version information associated with a node of the distributed balanced tree is retrieved. Validity of a lookup transaction performed on the balanced tree is determined by verifying a version value of only the leaf node accessed during the lookup operation against the retrieved version information.

Abstract: A method of operating a query system includes retrieving objects from a data source, wherein each of the retrieved objects includes (i) data and (ii) metadata describing the data. The method includes dynamically creating a cumulative schema by inferring a schema from each of the retrieved objects and merging the inferred schema with the cumulative schema. The method includes storing the data of each of the retrieved objects in a storage service. The method includes receiving, from a user, a query, and responding to the query based on data stored by the storage service.

Abstract: A distributed balanced tree having a plurality of nodes distributed across a plurality of servers is accessed. Version information associated with a node of the distributed balanced tree is retrieved. Validity of a lookup transaction performed on the balanced tree is determined by verifying a version value of only the leaf node accessed during the lookup operation against the retrieved version information.