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<section class="index">
<div class="index__hero">
<h1 class="index__h1"><strong>Sequel:</strong> The Database Toolkit for Ruby</h1>
</div>
<ul class="index__ul">
<li class="index__li">Thread safety, connection pooling and a concise DSL for constructing SQL queries and table schemas.</li>
<li class="index__li">Comprehensive ORM layer for mapping records to Ruby objects and handling associated records.</li>
<li class="index__li">Advanced database features such as prepared statements, bound variables, stored procedures, savepoints, two-phase commit, transaction isolation, primary/replica configurations, and database sharding.</li>
<li class="index__li">With adapters for ADO, Amalgalite, IBM_DB, JDBC, MySQL, Mysql2, ODBC, Oracle, PostgreSQL, SQLAnywhere, SQLite3, and TinyTDS.</li>
</ul>
<a name="example"></a>
<pre class="pre"><code class="ruby" lang="ruby"><span class="ident">require</span> <span class="punct">"</span><span class="string">sequel</span><span class="punct">"</span>
<span class="comment"># connect to an in-memory database</span>
<span class="constant">DB</span> <span class="punct">=</span> <span class="constant">Sequel</span><span class="punct">.</span><span class="ident">sqlite</span>
<span class="comment"># create an items table</span>
<span class="constant">DB</span><span class="punct">.</span><span class="ident">create_table</span> <span class="symbol">:items</span> <span class="keyword">do</span>
<span class="ident">primary_key</span> <span class="symbol">:id</span>
<span class="ident">String</span> <span class="symbol">:name</span><span class="punct">,</span> <span class="symbol">unique:</span> <span class="keyword">true</span><span class="punct">,</span> <span class="symbol">null:</span> <span class="keyword">false</span>
<span class="ident">Float</span> <span class="symbol">:price</span><span class="punct">,</span> <span class="symbol">null:</span> <span class="keyword">false</span>
<span class="keyword">end</span>
<span class="comment"># create a dataset from the items table</span>
<span class="ident">items</span> <span class="punct">=</span> <span class="constant">DB</span><span class="punct">[</span><span class="symbol">:items</span><span class="punct">]</span>
<span class="comment"># populate the table</span>
<span class="ident">items</span><span class="punct">.</span><span class="ident">insert</span><span class="punct">(</span><span class="symbol">name:</span> <span class="punct">'</span><span class="string">abc</span><span class="punct">',</span> <span class="symbol">price:</span> <span class="ident">rand</span> <span class="punct">*</span> <span class="number">100</span><span class="punct">)</span>
<span class="ident">items</span><span class="punct">.</span><span class="ident">insert</span><span class="punct">(</span><span class="symbol">name:</span> <span class="punct">'</span><span class="string">def</span><span class="punct">',</span> <span class="symbol">price:</span> <span class="ident">rand</span> <span class="punct">*</span> <span class="number">100</span><span class="punct">)</span>
<span class="ident">items</span><span class="punct">.</span><span class="ident">insert</span><span class="punct">(</span><span class="symbol">name:</span> <span class="punct">'</span><span class="string">ghi</span><span class="punct">',</span> <span class="symbol">price:</span> <span class="ident">rand</span> <span class="punct">*</span> <span class="number">100</span><span class="punct">)</span>
<span class="comment"># print out the number of records</span>
<span class="ident">puts</span> <span class="punct">"</span><span class="string">Item count: <span class="expr">#{items.count}</span></span><span class="punct">"</span>
<span class="comment"># print out the average price</span>
<span class="ident">puts</span> <span class="punct">"</span><span class="string">The average price is: <span class="expr">#{items.avg(:price)}</span></span><span class="punct">"</span></code></pre>
</section>
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