The .XUPPER command lets DSR control the case of index entries.
    If .XUPPER is in effect (as it is by default), DSR capitalizes
    the first character of every index entry and drops everything
    else in the entry to lowercase.
    See also the .XLOWER command.
    Formats
      .XUPPER
    Abreviated formats
      .XU
Additional Information:
explode
extract