Sql Excel : Picturing Data Analysis Using Dataflows

Tables store data, but tables do not actually do anything. Tables are nouns;
queries are verbs. This book mates SQL and Excel for data manipulation,
transformation, and presentation. The differences between these tools are
exacerbated because they often support the same operations, although in very
different ways. For instance, SQL uses the GROUP BY clause to summarize data in
groups. An Excel user, on the other hand, might use pivot tables, use the subtotal
wizard, or manually do calculations using functions such as SUMIF(); however,
nothing in Excel is called “group by.”
Because this book intends to combine the two technologies, it is useful to have a
common way of expressing data manipulations and data transformations, a
common language independent of the tools being used. Dataflows provide this
common language by showing the transformation operations fitting together like
an architecture blueprint for data processing, a blueprint that describes what
needs to be done, without saying which tool is going to do the work. This makes
dataflows a powerful mechanism for thinking about data transformations.