Google Fusion Tables is a service optimized for large data sets, so you can import tables of up to 100MB. The goal of Fusion Tables is to manage larger amounts of data than spreadsheets typically do. This size difference leads to a focus on a different set of functionalities. For example, Fusion Tables focuses more on bulk operations on the data (filtering, aggregation, merges). These operations are typically not necessary for smaller collections of data stored in spreadsheets. In contrast, spreadsheets preserve complete flexibility in managing data -- you can put any value you want in any cell and work carefully to format your spreadsheet to make it look nice," explains the FAQ.
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