Abstract: Disclosed are embodiments for replacing database table join keys with index keys. In one embodiment, a method is disclosed comprising: receiving, by a processor, annotation data, the annotation data comprising a set of rows; retrieving, by the processor, a root dataset, the root dataset stored in one or more files; generating, by the processor, a row identifier for each row in the set of rows, the row identifier storing a plurality of fields enabling alignment of a respective row in the annotation data to a corresponding row in the root dataset; generating, by the processor, an annotation dataset, the annotation dataset comprising the set of rows and corresponding row identifiers; and writing, by the processor, the annotation dataset to at least one file, the at least one file separate from the one or more files.

Abstract: Disclosed are embodiments for generating metadata files for composite datasets. In one embodiment, a method is disclosed comprising generating a tree representing a plurality of datasets; parsing the tree into an algebraic representation of the tree; identifying a plurality of terms in the algebraic representation, each term in the terms comprising at least two factors, each of the two factors associated with a dataset in the plurality of datasets; generating a metadata object of the plurality of terms; serializing the metadata object to generate serialized terms; and storing the serialized terms in a metadata file associated with the plurality of datasets.

Abstract: Disclosed embodiments are methods, apparatuses, and computer-readable media for annotating distributed data without redundant data copying. In one embodiment, a method is disclosed comprising reading a raw dataset, the raw dataset comprising a first set of columns and a first set of rows; generating an annotation dataset, the annotation dataset comprising a second set of columns and a second set of rows; assigning row identifiers to each row in the second set of rows, the row identifiers aligning the second set of rows with the first set of rows based on the underlying storage of the raw dataset and annotation dataset; and writing the annotation dataset to a distributed storage medium.