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Peter Croft (Project Manager, Unilever Computer Services Limited, 5 St. Johns Lane, London EC 1M 4BH, England)
G.R. Allen (Information Systems Manager, Library and Information Services, Unilever Research Laboratory, Colworth House, Sharnbrook, Bedford, England)

Program: electronic library and information systems

ISSN: 0033-0337

Article publication date: 1 March 1982



DECO is a textual database system for online searching and retrieval of documents, combined with offline index production. DECO is available from Unilever Computer Services Limited (UCSL) as a software package for Prime & Harris computers or as a bureau service. The design approach adopted for the software package enables it to be readily adapted for other host machines. The features of the system include both direct searching of an inverted file, derived from source data by means of one or more key extraction routines chosen by the user, and string searching of the text of retrieved document sets for both text strings and numeric values and ranges. In both cases, sophisticated truncation and masking facilities are available. All the keys in the inverted files or any subset of them may be displayed for selection online. Full Boolean logic and brackets may be used in combining search terms and/or previous search result sets. Retrieved document sets may be displayed either online or offline in formats determined by the user, and may be sorted prior to display to meet specific user needs. The whole database or any subset resulting from an online search can be made available for offline KWAC index production, using specified keys and user‐defined formats. Search strategies or groups of search terms can be saved using macros which offer permanent or temporary storage from which searches can be re‐executed. Switching between databases is easily achieved online.


Croft, P. and Allen, G.R. (1982), "DECO", Program: electronic library and information systems, Vol. 16 No. 3, pp. 158-170.




Copyright © 1982, MCB UP Limited

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