"group by is used to organize the date before other clauses - such as where, order by and functions...",really? Ref: Learning MySQL
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"group by is used to organize the date before other clauses - such as where, order by and functions -are applied. In contrast, order by is applied last- after the query has been resolved -to reorganize the query output for display.",really? Ref: Learning MySQL

I have surfed the net regarding this but nothing says anything like this.
Is this an error in book?