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    <p>This is the difference between accessing the name and <a href="http://docs.python.org/reference/executionmodel.html" rel="noreferrer">binding</a> it within a scope.</p> <p>If you're just looking up a variable to read its value, you've got access to global as well as local scope.</p> <p>However if you assign to a variable who's name isn't in local scope, you are <em>binding</em> that name into this scope (and if that name also exists as a global, you'll hide that). </p> <p>If you want to be able to assign to the global name, you need to tell the parser to use the global name rather than bind a new local name - which is what the 'global' keyword does.</p> <p>Binding anywhere within a block causes the name everywhere in that block to become bound, which can cause some rather odd looking consequences (e.g. UnboundLocalError suddenly appearing in previously working code).</p> <pre><code>&gt;&gt;&gt; a = 1 &gt;&gt;&gt; def p(): print(a) # accessing global scope, no binding going on &gt;&gt;&gt; def q(): a = 3 # binding a name in local scope - hiding global print(a) &gt;&gt;&gt; def r(): print(a) # fail - a is bound to local scope, but not assigned yet a = 4 &gt;&gt;&gt; p() 1 &gt;&gt;&gt; q() 3 &gt;&gt;&gt; r() Traceback (most recent call last): File "&lt;pyshell#35&gt;", line 1, in &lt;module&gt; r() File "&lt;pyshell#32&gt;", line 2, in r print(a) # fail - a is bound to local scope, but not assigned yet UnboundLocalError: local variable 'a' referenced before assignment &gt;&gt;&gt; </code></pre>
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Guidance
A row detail

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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