6.6Data Query Language (DQL)

Data Query Language (DQL) is, generally speaking, syntax for retrieving data stored in structures. In HDFql, the DQL is composed of only one operation (SELECT). It enables retrieval (i.e. reading) of data stored in HDF5 datasets or attributes, optionally according to certain criteria, such as hyperslab selections. Moreover, it supports both PROCESSING and REDIRECTING options to further transform and redirect the result of the operation according to the programmer’s needs.