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    <p>The destructor of A will run when its lifetime is over. If you want its memory to be freed and the destructor run, you have to delete it if it was allocated on the heap. If it was allocated on the stack this happens automatically (i.e. when it goes out of scope; see RAII). If it is a member of a class (not a pointer, but a full member), then this will happen when the containing object is destroyed.</p> <pre><code>class A { char *someHeapMemory; public: A() : someHeapMemory(new char[1000]) {} ~A() { delete[] someHeapMemory; } }; class B { A* APtr; public: B() : APtr(new A()) {} ~B() { delete APtr; } }; class C { A Amember; public: C() : Amember() {} ~C() {} // A is freed / destructed automatically. }; int main() { B* BPtr = new B(); delete BPtr; // Calls ~B() which calls ~A() C *CPtr = new C(); delete CPtr; B b; C c; } // b and c are freed/destructed automatically </code></pre> <p>In the above example, every delete and delete[] is needed. And no delete is needed (or indeed able to be used) where I did not use it.</p> <p><code>auto_ptr</code>, <code>unique_ptr</code> and <code>shared_ptr</code> etc... are great for making this lifetime management much easier:</p> <pre><code>class A { shared_array&lt;char&gt; someHeapMemory; public: A() : someHeapMemory(new char[1000]) {} ~A() { } // someHeapMemory is delete[]d automatically }; class B { shared_ptr&lt;A&gt; APtr; public: B() : APtr(new A()) {} ~B() { } // APtr is deleted automatically }; int main() { shared_ptr&lt;B&gt; BPtr = new B(); } // BPtr is deleted automatically </code></pre>
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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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