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    <p>When you call <code>open</code> you are opening the file anew and starting from the first line. Every time you call <code>readline</code> on an already open file it moves its internal "pointer" to the start of the next line. However, if you re-open the file the "pointer" is also re-initialized - and when you call <code>readline</code> it reads the first line again.</p> <p>Imagine that <code>open</code> returned a <code>file</code> object that looked like this:</p> <pre><code>class File(object): """Instances of this class are returned by `open` (pretend)""" def __init__(self, filesystem_handle): """Called when the file object is initialized by `open`""" print "Starting up a new file instance for {file} pointing at position 0.".format(...) self.position = 0 self.handle = filesystem_handle def readline(self): """Read a line. Terribly naive. Do not use at home" i = self.position c = None line = "" while c != "\n": c = self.handle.read_a_byte() line += c print "Read line from {p} to {end} ({i} + {p})".format(...) self.position += i return line </code></pre> <p>When you ran your first example you would get something like the following output:</p> <pre><code>Starting up a new file instance for /my-textfile.txt pointing at position 0. Read line from 0 to 80 (80 + 0) Read line from 80 to 160 (80 + 80) </code></pre> <p>While the output of your second example would look something like this:</p> <pre><code>Starting up a new file instance for /my-textfile.txt pointing at position 0. Read line from 0 to 80 (80 + 0) Starting up a new file instance for /my-textfile.txt pointing at position 0. Read line from 0 to 80 (80 + 0) </code></pre>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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