This book takes a rather unique approach to introducing SQL. Instead of picking a particular implementation of SQL and instead of introducing the parts of the language in the order they are written, this book deals with things in the order that SQL actually processes things.
This is an excellent book on SQL for beginners because it includes just about everything that a beginner needs to know in order to be able to write calls that actually use a database without getting them bogged down in too much detail on those parts of SQL that are more the province of the database administrator. The data definition area is covered in sufficient detail to allow someone who is doing everything themselves to be able to do that part of the job too without making things overly complicated.
This book rightly places the manipulation of the data (which is an ongoing process) ahead of data definition (which is only done once at the start and which is dependent on how you intend to work with it). The larger part of the book deals specifically with the select command which is the one which will see the most use and which is also the one with the most powerful options.
Even someone who has been writing SQL for some time should benefit from the clear and easy to follow explanations of what the main parts of SQL do in order to make their use of the language much more efficient.
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