cql - A Flat File Database Query Language
نویسنده
چکیده
cql is a UNIX system tool that applies C style query expressions to flat file databases. In some respects it is yet another addition to the toolbox of programmable file filters: grep [Hume88], sh [Bour78][BK89], awk [AKW88], and perl [Wall]. However, by restricting its problem domain, cql takes advantage of optimizations not available to these more general purpose tools. This paper describes the cql data description and query language, query optimizations, and provides comparisons with other tools.
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