Someone always says this, but starting with cat sure makes it easier compose the command line. When working with big files, start with "head -1000 | sort | uniq

Someone always says this, but starting with cat sure makes it easier compose the command line. When working with big files, start with "head -1000 | sort | uniq ..." and switch to cat after you work out the command. Or you start composing the command and realize you need to sort on field 2, so insert a "cut" before the "sort" etc.