Back to basics: The very clever history of the ROWID

The Spoken Nerd - A podcast by connormcdonald

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The ROWID underpins many forms of data access within the Oracle Database. If you're a newcomer to Oracle, querying the rowid from a table returns a cryptic string such as "AAAhDyABAAABd0SAAA". But head back into the earlier versions of the database, and querying the rowid would return a completely different format like "0005DD12.0000.0040". In this episode, I'll cover what the rowid is, why the format of the rowid has evolved over the years, and reveal the extremely clever way this evolution occurred - an evolution that allowed the rowid to store more information in the same number of bytes, and as a result, gave rise to multi-petabyte databases. You can also get a video version of the details in this episode on my YouTube channel here