A method includes obtaining a query containing at least one field from which data is being queried, obtaining a dataset having a schema-free data exchange format having multiple fields of data at different physical positions in the dataset, and parsing the dataset by obtaining a structural index that maps logical locations of fields to physical locations of the fields of the dataset, accessing the structural index with logical locations of the fields that index to the physical locations, and providing data from the fields based on the physical locations responsive to the query.