The ACCESS Query Language (AQL) is a D3 facility used to retrieve and output data and consists of the List preprocessor, the Select processor, and the Output processor. AQL is a system-level information retrieval language that allows users to query their database without writing complex programs.

AQL uses TCL commands and displays the results either on terminals or printers. AQL operates on specified files and items based on various optional criteria, specifications, modifiers, limiters, and options.