Yasushi Azumatani

Index-Free Full-Text Search Function Installed into Optical Disk Drive

An optical disk drive, equipped with additional SCSI commands for full-text search is developed. By hierarchical search architecture of parallel hardware, firmware and software, the system filters information almost at the disk-read speed. The basic search process is executed by a search engine sharing the function with a portion of the error-correcting LSI installed into the optical disk controller. The basic search performance of the developed system is 10 to 25 times faster than that of software. Also, introduction of an associative table for presearching results in performance more than 1000 times faster than that in the case in which no objective lines are found. Though our system does not have large-scale special-purpose hardware for text search, the retrieving speed of the free-text database is dramatically improved.