1One example is analytics.
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3Lets say you want to build the next Google Analytics. You figure out you want to track IP Address, Browser & Device type. Later you, however, finds out you might want to track Browser Size as well. Since analytics databases can contain millions/billions of data, it isn't so easy to add an extra column to your table. It would simply take too long.
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5With a NOSQL solution you might just add it to the future rows, without having to change every row in the tracking table.
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7So in general "every" place where you need to crunch data and numbers for report