Message 60

[Scan] What does it do?

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Message-ID: <3BC0BD10.483F2DAC@cs.cmu.edu>
Date: Sun, 07 Oct 2001 16:37:36 -0400
From: Jia Yu <jypan+@cs.cmu.edu>
Organization: School of Computer Science, Carnegie Mellon University
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To: post+academic.cs.15-721@andrew.cmu.edu, jypan@cs.cmu.edu
Subject: [Scan] What does it do?
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Hello,
   What does the Scan object do?
   (1) Does it points to the place corresponds to 
(first directory page, first directory record, first data page, first
data record) 
when it starts?
   (2) Does our myScan object need to maintain the key variables
ourselves?

   (3) getNext() return the informatioin of the NEXT record.
    Does this mean that we first advance the 'cursor' and then 
    return the information of the next record?
    If true, then how do we return the information of the first data
record, since we start at it and only can getNext().

Thank you.