I have found csvgrep to be the quickest way of extracting data from the OpenCellID dataset. For example, if you want to extract data for South Sudan which has a mobile country code (MCC) of 659, it would look like this:
csvgrep -c2 -m659 cell_towers.csv
where c indicates the column you want to search and m the value you want to grep for. Works with other columns too of course.
More info on csvgrep at
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