A data comparing means 41 compares the data on the bases 32-34 with each other and an abnormal data deciding means 42 decides an abnormal base data when no coincidence is obtained from said comparison. A data correcting means 43 uses the data on the data base having the highest weighting ...
In one embodiment index files with such error are renamed, serving to indicate that corresponding original files contain errors, and the error index files are automatically rebuilt whereby I/O error on the files causes no data loss. The index file rebuild does not invalidate access plans related...