HP 3000 Manuals HP 3000 Manuals
Chapter 1 INTRODUCING QUERY/V QUERY/V provides a simple method of accessing IMAGE data bases without programming effort. You can use QUERY to do the following: * enter data * modify or delete data values * retrieve data which meets selection criteria * report on the data retrieved You perform these operations by entering simple commands consisting of English keywords such as FIND and REPORT. You can request information about the function, format, and parameters of QUERY commands with the HELP command. All of the QUERY commands are discussed in Section 3. You only need to know the relationships of the data base elements and not the structure of the disc files. You can request information about the structure of the data bases with the FORM command. QUERY finds the data and performs the operations in response to your commands using the data base, data set, and data item names you specify. QUERY can be used either in session (interactive) mode or job (batch) mode. If you are using QUERY interactively at a terminal, QUERY prompts you for commands, issues error messages when an error occurs, and prints other information of interest to you. You can operate QUERY in job mode as an MPE job from an input device. In job mode, any error messages are printed on the $STDLIST device which is usually a line printer. QUERY adheres to all of the IMAGE security provisions described in the IMAGE Reference Manual. You must enter a valid password for the data base you want to use. This password determines which information you can access in the data base. QUERY report formatting capabilities enable you to design reports with header and column labels, page numbers, and group labels. In addition, you can sort entries through multiple fields, as well as total, average, or count columns of numeric data values. A sequence of commands can be stored in a file and executed at any time by entering the XEQ command as part of a session or a job. A frequently used or complex command can be stored as an individual procedure in a file referred to as a Proc-file. The procedure name can then be used in place of the command parameters. If your local HP 3000 and a remote HP 3000 have Distributed Systems (DS/3000) capability, you can use QUERY to access IMAGE data bases residing on the remote computer and retrieve information to be used on the local system. Three methods of accessing a remote data base are described in Appendix C. QUERY allows you to write your own user-defined procedures in any programming language which enable a report to perform a specialized function not provided by QUERY. Refer to Appendix F for further discussion. All of the tasks except user-defined report procedures can be accomplished without programming. If you are developing programs which access IMAGE data bases through the IMAGE library procedures, QUERY makes an excellent debugging aid. You can alter the data base content using your program and then use QUERY to examine the data and determine the results of your programmed changes.