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32            <h2 class="title" style="clear: both"><a id="DBOpenFlags"></a>Database Open Flags</h2>
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38		The following are the flags that you may want to use at database open time.  
39		Note that this list is not exhaustive ��� it includes only those flags likely 
40		to be of interest for introductory, single-threaded
41		database applications. For a complete list of the flags available to you, see the 
42		
43		<i class="citetitle">Berkeley DB C++ API guide.</i>
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46        <h3 class="title">Note</h3>
47        <p>
48		To specify more than one flag on the call to 
49		
50        <span><tt class="methodname">Db::open()</tt>,</span>
51		you must bitwise inclusively OR them together:
52	</p>
53        <a id="c_db3"></a>
54        <pre class="programlisting">u_int32_t open_flags = DB_CREATE | DB_EXCL;</pre>
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60				<tt class="literal">DB_CREATE</tt>
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62            <p>
63				If the database does not currently exist, create it. By default, the database open 
64				fails if the database does not already exist.
65			</p>
66          </li>
67          <li>
68            <p>
69				<tt class="literal">DB_EXCL</tt>
70			</p>
71            <p>
72				Exclusive database creation. Causes the database open to fail if the database 
73				already exists.  This flag is only meaningful when used with 
74				<tt class="literal">DB_CREATE</tt>.
75			</p>
76          </li>
77          <li>
78            <p>
79				<tt class="literal">DB_RDONLY</tt>
80			</p>
81            <p>
82				Open the database for read operations only. Causes any subsequent database write 
83				operations to fail.
84			</p>
85          </li>
86          <li>
87            <p>
88				<tt class="literal">DB_TRUNCATE</tt>
89			</p>
90            <p>
91				Physically truncate (empty) the on-disk file that contains the database. 
92				Causes DB to delete all databases physically contained in that file.
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