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<div><h1>Database -- the class of all database files</h1>
<div class="single"><h2>Description</h2>
<div>A database file is just like a hash table, except both the keys and values have to be strings. In this example we create a database file, store a few entries, remove an entry with <a href="_remove.html" title="remove an entry from a hash table">remove</a>, close the file, and then remove the file.<table class="examples"><tr><td><pre>i1 : filename = temporaryFileName () | ".dbm"
o1 = /tmp/M2-22058-1.dbm</pre>
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<tr><td><pre>i2 : x = openDatabaseOut filename
o2 = /tmp/M2-22058-1.dbm
o2 : Database</pre>
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<tr><td><pre>i3 : x#"first" = "hi there"
o3 = hi there</pre>
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<tr><td><pre>i4 : x#"first"
o4 = hi there</pre>
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<tr><td><pre>i5 : x#"second" = "ho there"
o5 = ho there</pre>
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<tr><td><pre>i6 : scanKeys(x,print)
second
first</pre>
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<tr><td><pre>i7 : remove(x,"second")</pre>
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<tr><td><pre>i8 : scanKeys(x,print)
first</pre>
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<tr><td><pre>i9 : close x
o9 = 0</pre>
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<tr><td><pre>i10 : removeFile filename</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___Hash__Table.html" title="the class of all hash tables">HashTable</a> -- the class of all hash tables</span></li>
<li><span><a href="___String.html" title="the class of all strings">String</a> -- the class of all strings</span></li>
<li><span><a href="_remove__File.html" title="remove a file">removeFile</a> -- remove a file</span></li>
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<div class="waystouse"><h2>Functions and methods returning a database :</h2>
<ul><li><span>openDatabase(String), see <span><a href="_open__Database.html" title="open a database file">openDatabase</a> -- open a database file</span></span></li>
<li><span>openDatabaseOut(String), see <span><a href="_open__Database__Out.html" title="open a database file for writing">openDatabaseOut</a> -- open a database file for writing</span></span></li>
</ul>
<h2>Methods that use a database :</h2>
<ul><li><span><a href="___Database_sp_sh_sp__String.html" title="get value from database">Database # String</a> -- get value from database</span></li>
<li><span><a href="___Database_sp_sh_qu_sp__String.html" title="check for value in database">Database #? String</a> -- check for value in database</span></li>
<li><span>isOpen(Database), see <span><a href="_is__Open.html" title="whether a file or database is open">isOpen</a> -- whether a file or database is open</span></span></li>
<li><span>Manipulator Database, see <span><a href="___Manipulator.html" title="the class of all file manipulators">Manipulator</a> -- the class of all file manipulators</span></span></li>
<li><span>scanKeys(Database,Function), see <span><a href="_scan__Keys.html" title="apply a function to each key in a hash table or database">scanKeys</a> -- apply a function to each key in a hash table or database</span></span></li>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="___Database.html" title="the class of all database files">Database</a> is <span>a <a href="___Type.html">type</a></span>, with ancestor class <a href="___Thing.html" title="the class of all things">Thing</a>.</p>
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