PDP-11 operating systems
DATATRIEVE is a database query and report writer tool from Hewlett-Packard. It runs on the OpenVMS operating system, as well as several PDP-11 operating systems. DATATRIEVE's command structure is nearly plain English, and it is an early example of a Fourth Generation Language (4GL). It works against flat files, indexed files, and databases. Such data files are delimited using record definitions stored in the Common Data Dictionary (CDD), or in RMS files. DATATRIEVE is used at many OpenVMS installations.
DATATRIEVE was developed in the late 1970s and early 1980s by a team of software engineers at DEC's Central Commercial Engineering facilities in Merrimack and Nashua, New Hampshire, under database architect Jim Starkey. Many of the project's engineers went on to highly visible careers in database management and other software disciplines.
DATATRIEVE adopted the wombat as its notional mascot; the program's help file responded to “HELP WOMBAT” with factual information about real world wombats.
Examples of DATATRIEVE usage
DATATRIEVE queries and commands approach plain English sentence structure, though would not be considered natural language, since a precise sentence structure must be used: 
DTR> FOR FAMILIES WITH NUMBER_KIDS = 2
CON> PRINT KID_NAME, AGE OF KIDS WITH AGE GT 20
DATATRIEVE can also be used to modify data:
DTR> FOR FAMILIES MODIFY EACH_KID OF FIRST 1 KIDS
DATATRIEVE can also cross multiple datasets, creating joined data views:
DTR> PRINT NAME, TYPE, PRICE OF
CON> YACHTS CROSS OWNERS OVER TYPE
- "DATATRIEVE". OpenVMS Systems - Commercial software. Hewlett-Packard. Retrieved 2013-09-02.
- "DATATRIEVE 7.3 Software Product Description" (PDF). Hewlett-Packard. May 2006. Retrieved 2013-09-02.
- Joe H. Gallagher. "The DATATRIEVE Programmer". Retrieved 2013-09-02.
- Martin P.J. Zinser. "Datatrieve and Wombats". IBPhoenix. Retrieved 2013-09-02.