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<!DOCTYPE html>
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<title>Examples — Momoko 0.5.0 documentation</title>
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<div class="section" id="examples">
<span id="id1"></span><h1>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h1>
<p>Momoko offers a few ways to interact with the database. The first one is the
blocking client. This is just a small wrapper around Psycopg2. The other two
are asynchronous clients. The example code can be found on <a class="reference external" href="https://github.com/FSX/momoko/tree/master/examples">Github</a>. Only
relevant code is shown on this page.</p>
<div class="section" id="blocking">
<h2>Blocking<a class="headerlink" href="#blocking" title="Permalink to this headline">¶</a></h2>
<p>The blocking client:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="k">class</span> <span class="nc">BaseHandler</span><span class="p">(</span><span class="n">tornado</span><span class="o">.</span><span class="n">web</span><span class="o">.</span><span class="n">RequestHandler</span><span class="p">):</span>
<span class="nd">@property</span>
<span class="k">def</span> <span class="nf">db</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Create a database connection when a request handler is called</span>
<span class="c"># and store the connection in the application object.</span>
<span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="p">,</span> <span class="s">'db'</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">momoko</span><span class="o">.</span><span class="n">BlockingClient</span><span class="p">({</span>
<span class="s">'host'</span><span class="p">:</span> <span class="s">'localhost'</span><span class="p">,</span>
<span class="s">'database'</span><span class="p">:</span> <span class="s">'momoko'</span><span class="p">,</span>
<span class="s">'user'</span><span class="p">:</span> <span class="s">'frank'</span><span class="p">,</span>
<span class="s">'password'</span><span class="p">:</span> <span class="s">''</span><span class="p">,</span>
<span class="s">'min_conn'</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span>
<span class="s">'max_conn'</span><span class="p">:</span> <span class="mi">20</span><span class="p">,</span>
<span class="s">'cleanup_timeout'</span><span class="p">:</span> <span class="mi">10</span>
<span class="p">})</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span>
<span class="k">class</span> <span class="nc">SingleQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Besides using a with statement everyting is the same as the normal</span>
<span class="c"># Psycopg2 module</span>
<span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">connection</span> <span class="k">as</span> <span class="n">conn</span><span class="p">:</span>
<span class="n">cursor</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">cursor</span><span class="p">()</span>
<span class="n">cursor</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">'SELECT 42, 12, 40, 11;'</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s">'</span> <span class="o">%</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
</pre></div>
</div>
</div>
<div class="section" id="callback">
<h2>Callback<a class="headerlink" href="#callback" title="Permalink to this headline">¶</a></h2>
<p>The asynchronous client that uses callbacks:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="k">class</span> <span class="nc">BaseHandler</span><span class="p">(</span><span class="n">tornado</span><span class="o">.</span><span class="n">web</span><span class="o">.</span><span class="n">RequestHandler</span><span class="p">):</span>
<span class="nd">@property</span>
<span class="k">def</span> <span class="nf">db</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Create a database connection when a request handler is called</span>
<span class="c"># and store the connection in the application object.</span>
<span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="p">,</span> <span class="s">'db'</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">momoko</span><span class="o">.</span><span class="n">AsyncClient</span><span class="p">({</span>
<span class="s">'host'</span><span class="p">:</span> <span class="s">'localhost'</span><span class="p">,</span>
<span class="s">'database'</span><span class="p">:</span> <span class="s">'momoko'</span><span class="p">,</span>
<span class="s">'user'</span><span class="p">:</span> <span class="s">'frank'</span><span class="p">,</span>
<span class="s">'password'</span><span class="p">:</span> <span class="s">''</span><span class="p">,</span>
<span class="s">'min_conn'</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span>
<span class="s">'max_conn'</span><span class="p">:</span> <span class="mi">20</span><span class="p">,</span>
<span class="s">'cleanup_timeout'</span><span class="p">:</span> <span class="mi">10</span>
<span class="p">})</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span>
<span class="k">class</span> <span class="nc">SingleQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># One simple query</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">'SELECT 42, 12, 40, 11;'</span><span class="p">,</span> <span class="n">callback</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_on_response</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">_on_response</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cursor</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s">'</span> <span class="o">%</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">BatchQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># These queries are executed all at once and therefore they need to be</span>
<span class="c"># stored in an dictionary so you know where the resulting cursors</span>
<span class="c"># come from, because they won't arrive in the same order.</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">batch</span><span class="p">({</span>
<span class="s">'query1'</span><span class="p">:</span> <span class="p">[</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,</span> <span class="mi">56</span><span class="p">)],</span>
<span class="s">'query2'</span><span class="p">:</span> <span class="s">'SELECT 1, 2, 3, 4, 5;'</span><span class="p">,</span>
<span class="s">'query3'</span><span class="p">:</span> <span class="s">'SELECT 465767, 4567, 3454;'</span>
<span class="p">},</span> <span class="bp">self</span><span class="o">.</span><span class="n">_on_response</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">_on_response</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cursors</span><span class="p">):</span>
<span class="k">for</span> <span class="n">key</span><span class="p">,</span> <span class="n">cursor</span> <span class="ow">in</span> <span class="n">cursors</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s"> = </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()))</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">QueryChainHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Execute a list of queries in the order you specified</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">chain</span><span class="p">((</span>
<span class="p">[</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, 11;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,)],</span>
<span class="s">'SELECT 1, 2, 3, 4, 5;'</span>
<span class="p">),</span> <span class="bp">self</span><span class="o">.</span><span class="n">_on_response</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">_on_response</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cursors</span><span class="p">):</span>
<span class="k">for</span> <span class="n">cursor</span> <span class="ow">in</span> <span class="n">cursors</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
</pre></div>
</div>
</div>
<div class="section" id="tornado-s-gen">
<h2>Tornado’s gen<a class="headerlink" href="#tornado-s-gen" title="Permalink to this headline">¶</a></h2>
<p>And the asynchronous callback-based client using Tornado’s <a class="reference external" href="http://www.tornadoweb.org/documentation/gen.html">gen</a> module:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">tornado</span> <span class="kn">import</span> <span class="n">gen</span>
<span class="k">class</span> <span class="nc">BaseHandler</span><span class="p">(</span><span class="n">tornado</span><span class="o">.</span><span class="n">web</span><span class="o">.</span><span class="n">RequestHandler</span><span class="p">):</span>
<span class="nd">@property</span>
<span class="k">def</span> <span class="nf">db</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Create a database connection when a request handler is called</span>
<span class="c"># and store the connection in the application object.</span>
<span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="p">,</span> <span class="s">'db'</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">momoko</span><span class="o">.</span><span class="n">AsyncClient</span><span class="p">({</span>
<span class="s">'host'</span><span class="p">:</span> <span class="s">'localhost'</span><span class="p">,</span>
<span class="s">'database'</span><span class="p">:</span> <span class="s">'momoko'</span><span class="p">,</span>
<span class="s">'user'</span><span class="p">:</span> <span class="s">'frank'</span><span class="p">,</span>
<span class="s">'password'</span><span class="p">:</span> <span class="s">''</span><span class="p">,</span>
<span class="s">'min_conn'</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span>
<span class="s">'max_conn'</span><span class="p">:</span> <span class="mi">20</span><span class="p">,</span>
<span class="s">'cleanup_timeout'</span><span class="p">:</span> <span class="mi">10</span>
<span class="p">})</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">application</span><span class="o">.</span><span class="n">db</span>
<span class="k">class</span> <span class="nc">SingleQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="nd">@gen.engine</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># One simple query</span>
<span class="n">cursor</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">,</span> <span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, 11;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">25</span><span class="p">,))</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s">'</span> <span class="o">%</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">BatchQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="nd">@gen.engine</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># These queries are executed all at once and therefore they need to be</span>
<span class="c"># stored in an dictionary so you know where the resulting cursors</span>
<span class="c"># come from, because they won't arrive in the same order.</span>
<span class="n">cursors</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">batch</span><span class="p">,</span> <span class="p">{</span>
<span class="s">'query1'</span><span class="p">:</span> <span class="p">[</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,</span> <span class="mi">56</span><span class="p">)],</span>
<span class="s">'query2'</span><span class="p">:</span> <span class="s">'SELECT 1, 2, 3, 4, 5;'</span><span class="p">,</span>
<span class="s">'query3'</span><span class="p">:</span> <span class="s">'SELECT 465767, 4567, 3454;'</span>
<span class="p">})</span>
<span class="k">for</span> <span class="n">key</span><span class="p">,</span> <span class="n">cursor</span> <span class="ow">in</span> <span class="n">cursors</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s"> = </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()))</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">QueryChainHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="nd">@gen.engine</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="c"># Execute a list of queries in the order you specified</span>
<span class="n">cursors</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">chain</span><span class="p">,</span> <span class="p">(</span>
<span class="p">[</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, 11;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,)],</span>
<span class="s">'SELECT 1, 2, 3, 4, 5;'</span>
<span class="p">))</span>
<span class="k">for</span> <span class="n">cursor</span> <span class="ow">in</span> <span class="n">cursors</span><span class="p">:</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">MultiQueryHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="nd">@gen.engine</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="n">cursor1</span><span class="p">,</span> <span class="n">cursor2</span><span class="p">,</span> <span class="n">cursor3</span> <span class="o">=</span> <span class="k">yield</span> <span class="p">[</span>
<span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">,</span> <span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, 11;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">25</span><span class="p">,)),</span>
<span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">,</span> <span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,</span> <span class="mi">56</span><span class="p">)),</span>
<span class="n">gen</span><span class="o">.</span><span class="n">Task</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">,</span> <span class="s">'SELECT 465767, 4567, 3454;'</span><span class="p">)</span>
<span class="p">]</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 1 results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor1</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 2 results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor2</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 3 results: </span><span class="si">%s</span><span class="s">'</span> <span class="o">%</span> <span class="n">cursor3</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
<span class="k">class</span> <span class="nc">CallbackWaitHandler</span><span class="p">(</span><span class="n">BaseHandler</span><span class="p">):</span>
<span class="nd">@tornado.web.asynchronous</span>
<span class="nd">@gen.engine</span>
<span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, 11;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">25</span><span class="p">,),</span>
<span class="n">callback</span><span class="o">=</span><span class="p">(</span><span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Callback</span><span class="p">(</span><span class="s">'q1'</span><span class="p">)))</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">'SELECT 42, 12, </span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">;'</span><span class="p">,</span> <span class="p">(</span><span class="mi">23</span><span class="p">,</span> <span class="mi">56</span><span class="p">),</span>
<span class="n">callback</span><span class="o">=</span><span class="p">(</span><span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Callback</span><span class="p">(</span><span class="s">'q2'</span><span class="p">)))</span>
<span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">'SELECT 465767, 4567, 3454;'</span><span class="p">,</span>
<span class="n">callback</span><span class="o">=</span><span class="p">(</span><span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Callback</span><span class="p">(</span><span class="s">'q3'</span><span class="p">)))</span>
<span class="n">cursor1</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Wait</span><span class="p">(</span><span class="s">'q1'</span><span class="p">)</span>
<span class="n">cursor2</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Wait</span><span class="p">(</span><span class="s">'q2'</span><span class="p">)</span>
<span class="n">cursor3</span> <span class="o">=</span> <span class="k">yield</span> <span class="n">gen</span><span class="o">.</span><span class="n">Wait</span><span class="p">(</span><span class="s">'q3'</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 1 results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor1</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 2 results: </span><span class="si">%s</span><span class="s"><br>'</span> <span class="o">%</span> <span class="n">cursor2</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s">'Query 3 results: </span><span class="si">%s</span><span class="s">'</span> <span class="o">%</span> <span class="n">cursor3</span><span class="o">.</span><span class="n">fetchall</span><span class="p">())</span>
<span class="bp">self</span><span class="o">.</span><span class="n">finish</span><span class="p">()</span>
</pre></div>
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<h3>Momoko</h3>
<p>An asynchronous Psycopg2 wrapper for Tornado.</p>
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<li><a class="reference internal" href="#">Examples</a><ul>
<li><a class="reference internal" href="#blocking">Blocking</a></li>
<li><a class="reference internal" href="#callback">Callback</a></li>
<li><a class="reference internal" href="#tornado-s-gen">Tornado’s gen</a></li>
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