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<section id="sqlalchemy-in-flask">
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<h1>SQLAlchemy in Flask<a class="headerlink" href="#sqlalchemy-in-flask" title="Link to this heading">¶</a></h1>
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<p>Many people prefer <a class="reference external" href="https://www.sqlalchemy.org/">SQLAlchemy</a> for database access. In this case it’s
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encouraged to use a package instead of a module for your flask application
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and drop the models into a separate module (<a class="reference internal" href="packages.html"><span class="doc">Large Applications as Packages</span></a>). While that
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is not necessary, it makes a lot of sense.</p>
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<p>There are four very common ways to use SQLAlchemy. I will outline each
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of them here:</p>
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<section id="flask-sqlalchemy-extension">
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<h2>Flask-SQLAlchemy Extension<a class="headerlink" href="#flask-sqlalchemy-extension" title="Link to this heading">¶</a></h2>
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<p>Because SQLAlchemy is a common database abstraction layer and object
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relational mapper that requires a little bit of configuration effort,
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there is a Flask extension that handles that for you. This is recommended
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if you want to get started quickly.</p>
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<p>You can download <a class="reference external" href="https://flask-sqlalchemy.palletsprojects.com/">Flask-SQLAlchemy</a> from <a class="reference external" href="https://pypi.org/project/Flask-SQLAlchemy/">PyPI</a>.</p>
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</section>
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<section id="declarative">
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<h2>Declarative<a class="headerlink" href="#declarative" title="Link to this heading">¶</a></h2>
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<p>The declarative extension in SQLAlchemy is the most recent method of using
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SQLAlchemy. It allows you to define tables and models in one go, similar
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to how Django works. In addition to the following text I recommend the
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official documentation on the <a class="reference external" href="https://docs.sqlalchemy.org/en/latest/orm/extensions/declarative/">declarative</a> extension.</p>
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<p>Here’s the example <code class="file docutils literal notranslate"><span class="pre">database.py</span></code> module for your application:</p>
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<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">create_engine</span>
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<span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy.orm</span><span class="w"> </span><span class="kn">import</span> <span class="n">scoped_session</span><span class="p">,</span> <span class="n">sessionmaker</span><span class="p">,</span> <span class="n">declarative_base</span>
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<span class="n">engine</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span><span class="s1">'sqlite:////tmp/test.db'</span><span class="p">)</span>
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<span class="n">db_session</span> <span class="o">=</span> <span class="n">scoped_session</span><span class="p">(</span><span class="n">sessionmaker</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span>
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<span class="n">autoflush</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span>
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<span class="n">bind</span><span class="o">=</span><span class="n">engine</span><span class="p">))</span>
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<span class="n">Base</span> <span class="o">=</span> <span class="n">declarative_base</span><span class="p">()</span>
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<span class="n">Base</span><span class="o">.</span><span class="n">query</span> <span class="o">=</span> <span class="n">db_session</span><span class="o">.</span><span class="n">query_property</span><span class="p">()</span>
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<span class="k">def</span><span class="w"> </span><span class="nf">init_db</span><span class="p">():</span>
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<span class="c1"># import all modules here that might define models so that</span>
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<span class="c1"># they will be registered properly on the metadata. Otherwise</span>
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<span class="c1"># you will have to import them first before calling init_db()</span>
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<span class="kn">import</span><span class="w"> </span><span class="nn">yourapplication.models</span>
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<span class="n">Base</span><span class="o">.</span><span class="n">metadata</span><span class="o">.</span><span class="n">create_all</span><span class="p">(</span><span class="n">bind</span><span class="o">=</span><span class="n">engine</span><span class="p">)</span>
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<section id="subclassing-flask">
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<h1>Subclassing Flask<a class="headerlink" href="#subclassing-flask" title="Link to this heading">¶</a></h1>
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<p>The <a class="reference internal" href="../api.html#flask.Flask" title="flask.Flask"><code class="xref py py-class docutils literal notranslate"><span class="pre">Flask</span></code></a> class is designed for subclassing.</p>
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<p>For example, you may want to override how request parameters are handled to preserve their order:</p>
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<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">flask</span><span class="w"> </span><span class="kn">import</span> <span class="n">Flask</span><span class="p">,</span> <span class="n">Request</span>
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<span class="kn">from</span><span class="w"> </span><span class="nn">werkzeug.datastructures</span><span class="w"> </span><span class="kn">import</span> <span class="n">ImmutableOrderedMultiDict</span>
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<span class="k">class</span><span class="w"> </span><span class="nc">MyRequest</span><span class="p">(</span><span class="n">Request</span><span class="p">):</span>
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<span class="w"> </span><span class="sd">"""Request subclass to override request parameter storage"""</span>
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<span class="n">parameter_storage_class</span> <span class="o">=</span> <span class="n">ImmutableOrderedMultiDict</span>
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<span class="k">class</span><span class="w"> </span><span class="nc">MyFlask</span><span class="p">(</span><span class="n">Flask</span><span class="p">):</span>
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<span class="w"> </span><span class="sd">"""Flask subclass using the custom request class"""</span>
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<span class="n">request_class</span> <span class="o">=</span> <span class="n">MyRequest</span>
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</pre></div>
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</div>
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<p>To define your models, just subclass the <code class="code docutils literal notranslate"><span class="pre">Base</span></code> class that was created by
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the code above. If you are wondering why we don’t have to care about
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threads here (like we did in the SQLite3 example above with the
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<a class="reference internal" href="../api.html#flask.g" title="flask.g"><code class="xref py py-data docutils literal notranslate"><span class="pre">g</span></code></a> object): that’s because SQLAlchemy does that for us
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already with the <a class="reference external" href="https://docs.sqlalchemy.org/en/20/orm/contextual.html#sqlalchemy.orm.scoped_session" title="(in SQLAlchemy v2.0)"><code class="xref py py-class docutils literal notranslate"><span class="pre">scoped_session</span></code></a>.</p>
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<p>To use SQLAlchemy in a declarative way with your application, you just
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have to put the following code into your application module. Flask will
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automatically remove database sessions at the end of the request or
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when the application shuts down:</p>
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<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">db_session</span>
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<span class="nd">@app</span><span class="o">.</span><span class="n">teardown_appcontext</span>
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<span class="k">def</span><span class="w"> </span><span class="nf">shutdown_session</span><span class="p">(</span><span class="n">exception</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
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<span class="n">db_session</span><span class="o">.</span><span class="n">remove</span><span class="p">()</span>
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</pre></div>
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</div>
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<p>Here is an example model (put this into <code class="file docutils literal notranslate"><span class="pre">models.py</span></code>, e.g.):</p>
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<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">Column</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">String</span>
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<span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">Base</span>
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<span class="k">class</span><span class="w"> </span><span class="nc">User</span><span class="p">(</span><span class="n">Base</span><span class="p">):</span>
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<span class="n">__tablename__</span> <span class="o">=</span> <span class="s1">'users'</span>
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<span class="nb">id</span> <span class="o">=</span> <span class="n">Column</span><span class="p">(</span><span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
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<span class="n">name</span> <span class="o">=</span> <span class="n">Column</span><span class="p">(</span><span class="n">String</span><span class="p">(</span><span class="mi">50</span><span class="p">),</span> <span class="n">unique</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
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<span class="n">email</span> <span class="o">=</span> <span class="n">Column</span><span class="p">(</span><span class="n">String</span><span class="p">(</span><span class="mi">120</span><span class="p">),</span> <span class="n">unique</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
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<span class="k">def</span><span class="w"> </span><span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">email</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
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<span class="bp">self</span><span class="o">.</span><span class="n">name</span> <span class="o">=</span> <span class="n">name</span>
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<span class="bp">self</span><span class="o">.</span><span class="n">email</span> <span class="o">=</span> <span class="n">email</span>
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<span class="k">def</span><span class="w"> </span><span class="fm">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
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<span class="k">return</span> <span class="sa">f</span><span class="s1">'<User </span><span class="si">{</span><span class="bp">self</span><span class="o">.</span><span class="n">name</span><span class="si">!r}</span><span class="s1">>'</span>
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</pre></div>
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</div>
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<p>To create the database you can use the <code class="code docutils literal notranslate"><span class="pre">init_db</span></code> function:</p>
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<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">init_db</span>
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<span class="gp">>>> </span><span class="n">init_db</span><span class="p">()</span>
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</pre></div>
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</div>
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<p>You can insert entries into the database like this:</p>
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<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">db_session</span>
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<span class="gp">>>> </span><span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.models</span><span class="w"> </span><span class="kn">import</span> <span class="n">User</span>
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<span class="gp">>>> </span><span class="n">u</span> <span class="o">=</span> <span class="n">User</span><span class="p">(</span><span class="s1">'admin'</span><span class="p">,</span> <span class="s1">'admin@localhost'</span><span class="p">)</span>
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<span class="gp">>>> </span><span class="n">db_session</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">u</span><span class="p">)</span>
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<span class="gp">>>> </span><span class="n">db_session</span><span class="o">.</span><span class="n">commit</span><span class="p">()</span>
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</pre></div>
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</div>
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<p>Querying is simple as well:</p>
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<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">User</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">all</span><span class="p">()</span>
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<span class="go">[<User 'admin'>]</span>
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<span class="gp">>>> </span><span class="n">User</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">User</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s1">'admin'</span><span class="p">)</span><span class="o">.</span><span class="n">first</span><span class="p">()</span>
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<span class="go"><User 'admin'></span>
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</pre></div>
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</div>
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</section>
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<section id="manual-object-relational-mapping">
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<h2>Manual Object Relational Mapping<a class="headerlink" href="#manual-object-relational-mapping" title="Link to this heading">¶</a></h2>
|
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<p>Manual object relational mapping has a few upsides and a few downsides
|
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versus the declarative approach from above. The main difference is that
|
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you define tables and classes separately and map them together. It’s more
|
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flexible but a little more to type. In general it works like the
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declarative approach, so make sure to also split up your application into
|
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multiple modules in a package.</p>
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<p>Here is an example <code class="file docutils literal notranslate"><span class="pre">database.py</span></code> module for your application:</p>
|
||||
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">create_engine</span><span class="p">,</span> <span class="n">MetaData</span>
|
||||
<span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy.orm</span><span class="w"> </span><span class="kn">import</span> <span class="n">scoped_session</span><span class="p">,</span> <span class="n">sessionmaker</span>
|
||||
|
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<span class="n">engine</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span><span class="s1">'sqlite:////tmp/test.db'</span><span class="p">)</span>
|
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<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
|
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<span class="n">db_session</span> <span class="o">=</span> <span class="n">scoped_session</span><span class="p">(</span><span class="n">sessionmaker</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span>
|
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<span class="n">autoflush</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span>
|
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<span class="n">bind</span><span class="o">=</span><span class="n">engine</span><span class="p">))</span>
|
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<span class="k">def</span><span class="w"> </span><span class="nf">init_db</span><span class="p">():</span>
|
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<span class="n">metadata</span><span class="o">.</span><span class="n">create_all</span><span class="p">(</span><span class="n">bind</span><span class="o">=</span><span class="n">engine</span><span class="p">)</span>
|
||||
</pre></div>
|
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</div>
|
||||
<p>As in the declarative approach, you need to close the session after
|
||||
each request or application context shutdown. Put this into your
|
||||
application module:</p>
|
||||
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">db_session</span>
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|
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<span class="nd">@app</span><span class="o">.</span><span class="n">teardown_appcontext</span>
|
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<span class="k">def</span><span class="w"> </span><span class="nf">shutdown_session</span><span class="p">(</span><span class="n">exception</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
|
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<span class="n">db_session</span><span class="o">.</span><span class="n">remove</span><span class="p">()</span>
|
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</pre></div>
|
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</div>
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<p>Here is an example table and model (put this into <code class="file docutils literal notranslate"><span class="pre">models.py</span></code>):</p>
|
||||
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">String</span>
|
||||
<span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy.orm</span><span class="w"> </span><span class="kn">import</span> <span class="n">mapper</span>
|
||||
<span class="kn">from</span><span class="w"> </span><span class="nn">yourapplication.database</span><span class="w"> </span><span class="kn">import</span> <span class="n">metadata</span><span class="p">,</span> <span class="n">db_session</span>
|
||||
|
||||
<span class="k">class</span><span class="w"> </span><span class="nc">User</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
|
||||
<span class="n">query</span> <span class="o">=</span> <span class="n">db_session</span><span class="o">.</span><span class="n">query_property</span><span class="p">()</span>
|
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|
||||
<span class="k">def</span><span class="w"> </span><span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">email</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
|
||||
<span class="bp">self</span><span class="o">.</span><span class="n">name</span> <span class="o">=</span> <span class="n">name</span>
|
||||
<span class="bp">self</span><span class="o">.</span><span class="n">email</span> <span class="o">=</span> <span class="n">email</span>
|
||||
|
||||
<span class="k">def</span><span class="w"> </span><span class="fm">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
||||
<span class="k">return</span> <span class="sa">f</span><span class="s1">'<User </span><span class="si">{</span><span class="bp">self</span><span class="o">.</span><span class="n">name</span><span class="si">!r}</span><span class="s1">>'</span>
|
||||
|
||||
<span class="n">users</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s1">'users'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
|
||||
<span class="n">Column</span><span class="p">(</span><span class="s1">'id'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="kc">True</span><span class="p">),</span>
|
||||
<span class="n">Column</span><span class="p">(</span><span class="s1">'name'</span><span class="p">,</span> <span class="n">String</span><span class="p">(</span><span class="mi">50</span><span class="p">),</span> <span class="n">unique</span><span class="o">=</span><span class="kc">True</span><span class="p">),</span>
|
||||
<span class="n">Column</span><span class="p">(</span><span class="s1">'email'</span><span class="p">,</span> <span class="n">String</span><span class="p">(</span><span class="mi">120</span><span class="p">),</span> <span class="n">unique</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
|
||||
<span class="p">)</span>
|
||||
<span class="n">mapper</span><span class="p">(</span><span class="n">User</span><span class="p">,</span> <span class="n">users</span><span class="p">)</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>Querying and inserting works exactly the same as in the example above.</p>
|
||||
</section>
|
||||
<section id="sql-abstraction-layer">
|
||||
<h2>SQL Abstraction Layer<a class="headerlink" href="#sql-abstraction-layer" title="Link to this heading">¶</a></h2>
|
||||
<p>If you just want to use the database system (and SQL) abstraction layer
|
||||
you basically only need the engine:</p>
|
||||
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">create_engine</span><span class="p">,</span> <span class="n">MetaData</span><span class="p">,</span> <span class="n">Table</span>
|
||||
|
||||
<span class="n">engine</span> <span class="o">=</span> <span class="n">create_engine</span><span class="p">(</span><span class="s1">'sqlite:////tmp/test.db'</span><span class="p">)</span>
|
||||
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">(</span><span class="n">bind</span><span class="o">=</span><span class="n">engine</span><span class="p">)</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>Then you can either declare the tables in your code like in the examples
|
||||
above, or automatically load them:</p>
|
||||
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span><span class="w"> </span><span class="nn">sqlalchemy</span><span class="w"> </span><span class="kn">import</span> <span class="n">Table</span>
|
||||
|
||||
<span class="n">users</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s1">'users'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span> <span class="n">autoload</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>To insert data you can use the <code class="code docutils literal notranslate"><span class="pre">insert</span></code> method. We have to get a
|
||||
connection first so that we can use a transaction:</p>
|
||||
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">con</span> <span class="o">=</span> <span class="n">engine</span><span class="o">.</span><span class="n">connect</span><span class="p">()</span>
|
||||
<span class="gp">>>> </span><span class="n">con</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">users</span><span class="o">.</span><span class="n">insert</span><span class="p">(),</span> <span class="n">name</span><span class="o">=</span><span class="s1">'admin'</span><span class="p">,</span> <span class="n">email</span><span class="o">=</span><span class="s1">'admin@localhost'</span><span class="p">)</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>SQLAlchemy will automatically commit for us.</p>
|
||||
<p>To query your database, you use the engine directly or use a connection:</p>
|
||||
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">users</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">users</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="mi">1</span><span class="p">)</span><span class="o">.</span><span class="n">execute</span><span class="p">()</span><span class="o">.</span><span class="n">first</span><span class="p">()</span>
|
||||
<span class="go">(1, 'admin', 'admin@localhost')</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>These results are also dict-like tuples:</p>
|
||||
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">r</span> <span class="o">=</span> <span class="n">users</span><span class="o">.</span><span class="n">select</span><span class="p">(</span><span class="n">users</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="mi">1</span><span class="p">)</span><span class="o">.</span><span class="n">execute</span><span class="p">()</span><span class="o">.</span><span class="n">first</span><span class="p">()</span>
|
||||
<span class="gp">>>> </span><span class="n">r</span><span class="p">[</span><span class="s1">'name'</span><span class="p">]</span>
|
||||
<span class="go">'admin'</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>You can also pass strings of SQL statements to the
|
||||
<code class="xref py py-meth docutils literal notranslate"><span class="pre">execute()</span></code> method:</p>
|
||||
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">engine</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s1">'select * from users where id = :1'</span><span class="p">,</span> <span class="p">[</span><span class="mi">1</span><span class="p">])</span><span class="o">.</span><span class="n">first</span><span class="p">()</span>
|
||||
<span class="go">(1, 'admin', 'admin@localhost')</span>
|
||||
</pre></div>
|
||||
</div>
|
||||
<p>For more information about SQLAlchemy, head over to the
|
||||
<a class="reference external" href="https://www.sqlalchemy.org/">website</a>.</p>
|
||||
</section>
|
||||
<p>This is the recommended approach for overriding or augmenting Flask’s internal functionality.</p>
|
||||
</section>
|
||||
|
||||
|
||||
|
|
@ -250,31 +69,20 @@ connection first so that we can use a transaction:</p>
|
|||
<span id="sidebar-top"></span>
|
||||
<div class="sphinxsidebar" role="navigation" aria-label="Main">
|
||||
<div class="sphinxsidebarwrapper">
|
||||
|
||||
|
||||
|
||||
|
||||
<p class="logo"><a href="../index.html">
|
||||
<img class="logo" src="../_static/flask-vertical.png" alt="Logo of Flask"/>
|
||||
</a></p>
|
||||
|
||||
|
||||
<h3>Contents</h3>
|
||||
<ul>
|
||||
<li><a class="reference internal" href="#">SQLAlchemy in Flask</a><ul>
|
||||
<li><a class="reference internal" href="#flask-sqlalchemy-extension">Flask-SQLAlchemy Extension</a></li>
|
||||
<li><a class="reference internal" href="#declarative">Declarative</a></li>
|
||||
<li><a class="reference internal" href="#manual-object-relational-mapping">Manual Object Relational Mapping</a></li>
|
||||
<li><a class="reference internal" href="#sql-abstraction-layer">SQL Abstraction Layer</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
</ul>
|
||||
<h3>Navigation</h3>
|
||||
<ul>
|
||||
<li><a href="../index.html">Overview</a>
|
||||
<ul>
|
||||
<li><a href="index.html">Patterns for Flask</a>
|
||||
<ul>
|
||||
<li>Previous: <a href="sqlite3.html" title="previous chapter">Using SQLite 3 with Flask</a>
|
||||
<li>Next: <a href="fileuploads.html" title="next chapter">Uploading Files</a></ul>
|
||||
<li>Previous: <a href="celery.html" title="previous chapter">Background Tasks with Celery</a>
|
||||
<li>Next: <a href="singlepageapplications.html" title="next chapter">Single-Page Applications</a></ul>
|
||||
</li>
|
||||
</ul>
|
||||
</li>
|
||||
|
|
@ -298,4 +106,4 @@ connection first so that we can use a transaction:</p>
|
|||
Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 8.1.3.
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
</html>
|
||||
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|
|
|||
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