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  <div class="section" id="module-psycopg2">
<span id="the-psycopg2-module-content"></span><h1>The <a class="reference internal" href="#module-psycopg2" title="psycopg2"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2</span></tt></a> module content<a class="headerlink" href="#module-psycopg2" title="Permalink to this headline"></a></h1>
<p>The module interface respects the standard defined in the <a class="reference external" href="http://www.python.org/dev/peps/pep-0249/">DB API 2.0</a>.</p>
<span class="target" id="index-0"></span><dl class="function">
<dt id="psycopg2.connect">
<tt class="descclassname">psycopg2.</tt><tt class="descname">connect</tt><big>(</big><em>dsn or params [, connection_factory] [, async=0]</em><big>)</big><a class="headerlink" href="#psycopg2.connect" title="Permalink to this definition"></a></dt>
<dd><p>Create a new database session and return a new <a class="reference internal" href="connection.html#connection" title="connection"><tt class="xref py py-obj docutils literal"><span class="pre">connection</span></tt></a> object.</p>
<p>The connection parameters can be specified either as a string:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">conn</span> <span class="o">=</span> <span class="n">psycopg2</span><span class="o">.</span><span class="n">connect</span><span class="p">(</span><span class="s">&quot;dbname=test user=postgres password=secret&quot;</span><span class="p">)</span>
</pre></div>
</div>
<p>or using a set of keyword arguments:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">conn</span> <span class="o">=</span> <span class="n">psycopg2</span><span class="o">.</span><span class="n">connect</span><span class="p">(</span><span class="n">database</span><span class="o">=</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="n">user</span><span class="o">=</span><span class="s">&quot;postgres&quot;</span><span class="p">,</span> <span class="n">password</span><span class="o">=</span><span class="s">&quot;secret&quot;</span><span class="p">)</span>
</pre></div>
</div>
<p>The basic connection parameters are:</p>
<ul class="simple">
<li><tt class="xref py py-obj docutils literal"><span class="pre">dbname</span></tt> &#8211; the database name (only in dsn string)</li>
<li><tt class="xref py py-obj docutils literal"><span class="pre">database</span></tt> &#8211; the database name (only as keyword argument)</li>
<li><tt class="xref py py-obj docutils literal"><span class="pre">user</span></tt> &#8211; user name used to authenticate</li>
<li><tt class="xref py py-obj docutils literal"><span class="pre">password</span></tt> &#8211; password used to authenticate</li>
<li><tt class="xref py py-obj docutils literal"><span class="pre">host</span></tt> &#8211; database host address (defaults to UNIX socket if not provided)</li>
<li><tt class="xref py py-obj docutils literal"><span class="pre">port</span></tt> &#8211; connection port number (defaults to 5432 if not provided)</li>
</ul>
<p>Any other connection parameter supported by the client library/server can
be passed either in the connection string or as keyword. See the
PostgreSQL documentation for a complete <a class="reference external" href="http://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-PQCONNECTDBPARAMS">list of supported parameters</a>.
Also note that the same parameters can be passed to the client library
using <a class="reference external" href="http://www.postgresql.org/docs/current/static/libpq-envars.html">environment variables</a>.</p>
<p>Using the <em>connection_factory</em> parameter a different class or
connections factory can be specified. It should be a callable object
taking a <em>dsn</em> argument. See <a class="reference internal" href="advanced.html#subclassing-connection"><em>Connection and cursor factories</em></a> for
details.</p>
<p>Using <em>async</em>=1 an asynchronous connection will be created: see
<a class="reference internal" href="advanced.html#async-support"><em>Asynchronous support</em></a> to know about advantages and limitations.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 2.4.3: </span>any keyword argument is passed to the connection. Previously only the
basic parameters (plus <tt class="xref py py-obj docutils literal"><span class="pre">sslmode</span></tt>) were supported as keywords.</p>
</div>
<div class="admonition-db-api-extension dbapi-extension admonition">
<p class="first admonition-title">DB API extension</p>
<p class="last">The parameters <em>connection_factory</em> and <em>async</em> are Psycopg extensions
to the DB API 2.0.</p>
</div>
</dd></dl>

<dl class="data">
<dt id="psycopg2.apilevel">
<tt class="descclassname">psycopg2.</tt><tt class="descname">apilevel</tt><a class="headerlink" href="#psycopg2.apilevel" title="Permalink to this definition"></a></dt>
<dd><p>String constant stating the supported DB API level.  For <a class="reference internal" href="#module-psycopg2" title="psycopg2"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2</span></tt></a> is
<tt class="docutils literal"><span class="pre">2.0</span></tt>.</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.threadsafety">
<tt class="descclassname">psycopg2.</tt><tt class="descname">threadsafety</tt><a class="headerlink" href="#psycopg2.threadsafety" title="Permalink to this definition"></a></dt>
<dd><p>Integer constant stating the level of thread safety the interface
supports.  For <a class="reference internal" href="#module-psycopg2" title="psycopg2"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2</span></tt></a> is <tt class="docutils literal"><span class="pre">2</span></tt>, i.e. threads can share the module
and the connection. See <a class="reference internal" href="usage.html#thread-safety"><em>Thread and process safety</em></a> for details.</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.paramstyle">
<tt class="descclassname">psycopg2.</tt><tt class="descname">paramstyle</tt><a class="headerlink" href="#psycopg2.paramstyle" title="Permalink to this definition"></a></dt>
<dd><p>String constant stating the type of parameter marker formatting expected
by the interface.  For <a class="reference internal" href="#module-psycopg2" title="psycopg2"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2</span></tt></a> is <tt class="docutils literal"><span class="pre">pyformat</span></tt>.  See also
<a class="reference internal" href="usage.html#query-parameters"><em>Passing parameters to SQL queries</em></a>.</p>
</dd></dl>

<div class="section" id="exceptions">
<span id="dbapi-exceptions"></span><span id="index-1"></span><h2>Exceptions<a class="headerlink" href="#exceptions" title="Permalink to this headline"></a></h2>
<p>In compliance with the <a class="reference external" href="http://www.python.org/dev/peps/pep-0249/">DB API 2.0</a>, the module makes informations about errors
available through the following exceptions:</p>
<dl class="exception">
<dt id="psycopg2.Warning">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">Warning</tt><a class="headerlink" href="#psycopg2.Warning" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for important warnings like data truncations while
inserting, etc. It is a subclass of the Python <a class="reference external" href="/usr/share/doc/python2.7-doc/html/library/exceptions.html#exceptions.StandardError" title="(in Python v2.7)"><tt class="xref py py-obj docutils literal"><span class="pre">StandardError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.Error">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">Error</tt><a class="headerlink" href="#psycopg2.Error" title="Permalink to this definition"></a></dt>
<dd><p>Exception that is the base class of all other error exceptions. You can
use this to catch all errors with one single <tt class="xref py py-obj docutils literal"><span class="pre">except</span></tt> statement. Warnings
are not considered errors and thus not use this class as base. It
is a subclass of the Python <tt class="xref py py-obj docutils literal"><span class="pre">StandardError</span></tt>.</p>
<dl class="attribute">
<dt id="psycopg2.Error.pgerror">
<tt class="descname">pgerror</tt><a class="headerlink" href="#psycopg2.Error.pgerror" title="Permalink to this definition"></a></dt>
<dd><p>String representing the error message returned by the backend,
<tt class="xref py py-obj docutils literal"><span class="pre">None</span></tt> if not available.</p>
</dd></dl>

<dl class="attribute">
<dt id="psycopg2.Error.pgcode">
<tt class="descname">pgcode</tt><a class="headerlink" href="#psycopg2.Error.pgcode" title="Permalink to this definition"></a></dt>
<dd><p>String representing the error code returned by the backend, <tt class="xref py py-obj docutils literal"><span class="pre">None</span></tt>
if not available.  The <a class="reference internal" href="errorcodes.html#module-psycopg2.errorcodes" title="psycopg2.errorcodes"><tt class="xref py py-obj docutils literal"><span class="pre">errorcodes</span></tt></a> module contains
symbolic constants representing PostgreSQL error codes.</p>
</dd></dl>

<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">try</span><span class="p">:</span>
<span class="gp">... </span>    <span class="n">cur</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">&quot;SELECT * FROM barf&quot;</span><span class="p">)</span>
<span class="gp">... </span><span class="k">except</span> <span class="ne">Exception</span><span class="p">,</span> <span class="n">e</span><span class="p">:</span>
<span class="gp">... </span>    <span class="k">pass</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">e</span><span class="o">.</span><span class="n">pgcode</span>
<span class="go">&#39;42P01&#39;</span>
<span class="gp">&gt;&gt;&gt; </span><span class="k">print</span> <span class="n">e</span><span class="o">.</span><span class="n">pgerror</span>
<span class="go">ERROR:  relation &quot;barf&quot; does not exist</span>
<span class="go">LINE 1: SELECT * FROM barf</span>
<span class="go">                      ^</span>
</pre></div>
</div>
<dl class="attribute">
<dt id="psycopg2.Error.cursor">
<tt class="descname">cursor</tt><a class="headerlink" href="#psycopg2.Error.cursor" title="Permalink to this definition"></a></dt>
<dd><p>The cursor the exception was raised from; <a class="reference external" href="/usr/share/doc/python2.7-doc/html/library/constants.html#None" title="(in Python v2.7)"><tt class="xref py py-obj docutils literal"><span class="pre">None</span></tt></a> if not applicable.</p>
</dd></dl>

<div class="admonition-db-api-extension dbapi-extension admonition">
<p class="first admonition-title">DB API extension</p>
<p class="last">The <a class="reference internal" href="#psycopg2.Error.pgerror" title="psycopg2.Error.pgerror"><tt class="xref py py-obj docutils literal"><span class="pre">pgerror</span></tt></a>, <a class="reference internal" href="#psycopg2.Error.pgcode" title="psycopg2.Error.pgcode"><tt class="xref py py-obj docutils literal"><span class="pre">pgcode</span></tt></a>, and <a class="reference internal" href="#psycopg2.Error.cursor" title="psycopg2.Error.cursor"><tt class="xref py py-obj docutils literal"><span class="pre">cursor</span></tt></a> attributes
are Psycopg extensions.</p>
</div>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.InterfaceError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">InterfaceError</tt><a class="headerlink" href="#psycopg2.InterfaceError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for errors that are related to the database interface
rather than the database itself.  It is a subclass of <a class="reference internal" href="#psycopg2.Error" title="psycopg2.Error"><tt class="xref py py-obj docutils literal"><span class="pre">Error</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.DatabaseError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">DatabaseError</tt><a class="headerlink" href="#psycopg2.DatabaseError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for errors that are related to the database.  It is a
subclass of <a class="reference internal" href="#psycopg2.Error" title="psycopg2.Error"><tt class="xref py py-obj docutils literal"><span class="pre">Error</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.DataError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">DataError</tt><a class="headerlink" href="#psycopg2.DataError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for errors that are due to problems with the processed
data like division by zero, numeric value out of range, etc. It is a
subclass of <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.OperationalError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">OperationalError</tt><a class="headerlink" href="#psycopg2.OperationalError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for errors that are related to the database&#8217;s operation
and not necessarily under the control of the programmer, e.g. an
unexpected disconnect occurs, the data source name is not found, a
transaction could not be processed, a memory allocation error occurred
during processing, etc.  It is a subclass of <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.IntegrityError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">IntegrityError</tt><a class="headerlink" href="#psycopg2.IntegrityError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised when the relational integrity of the database is
affected, e.g. a foreign key check fails.  It is a subclass of
<a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.InternalError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">InternalError</tt><a class="headerlink" href="#psycopg2.InternalError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised when the database encounters an internal error, e.g. the
cursor is not valid anymore, the transaction is out of sync, etc.  It is a
subclass of <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.ProgrammingError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">ProgrammingError</tt><a class="headerlink" href="#psycopg2.ProgrammingError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised for programming errors, e.g. table not found or already
exists, syntax error in the SQL statement, wrong number of parameters
specified, etc.  It is a subclass of <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<dl class="exception">
<dt id="psycopg2.NotSupportedError">
<em class="property">exception </em><tt class="descclassname">psycopg2.</tt><tt class="descname">NotSupportedError</tt><a class="headerlink" href="#psycopg2.NotSupportedError" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised in case a method or database API was used which is not
supported by the database, e.g. requesting a <tt class="xref py py-obj docutils literal"><span class="pre">rollback()</span></tt> on a
connection that does not support transaction or has transactions turned
off.  It is a subclass of <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>.</p>
</dd></dl>

<div class="admonition-db-api-extension dbapi-extension admonition">
<p class="first admonition-title">DB API extension</p>
<p class="last">Psycopg may raise a few other, more specialized, exceptions: currently
<a class="reference internal" href="extensions.html#psycopg2.extensions.QueryCanceledError" title="psycopg2.extensions.QueryCanceledError"><tt class="xref py py-obj docutils literal"><span class="pre">QueryCanceledError</span></tt></a> and
<a class="reference internal" href="extensions.html#psycopg2.extensions.TransactionRollbackError" title="psycopg2.extensions.TransactionRollbackError"><tt class="xref py py-obj docutils literal"><span class="pre">TransactionRollbackError</span></tt></a> are defined. These
exceptions are not exposed by the main <tt class="xref py py-obj docutils literal"><span class="pre">psycopg2</span></tt> module but are
made available by the <a class="reference internal" href="extensions.html#module-psycopg2.extensions" title="psycopg2.extensions"><tt class="xref py py-obj docutils literal"><span class="pre">extensions</span></tt></a> module.  All the
additional exceptions are subclasses of standard DB API 2.0 exceptions, so
trapping them specifically is not required.</p>
</div>
<p>This is the exception inheritance layout:</p>
<pre class="literal-block">
<tt class="xref py py-obj docutils literal"><span class="pre">StandardError</span></tt>
|__ <a class="reference internal" href="#psycopg2.Warning" title="psycopg2.Warning"><tt class="xref py py-obj docutils literal"><span class="pre">Warning</span></tt></a>
|__ <a class="reference internal" href="#psycopg2.Error" title="psycopg2.Error"><tt class="xref py py-obj docutils literal"><span class="pre">Error</span></tt></a>
    |__ <a class="reference internal" href="#psycopg2.InterfaceError" title="psycopg2.InterfaceError"><tt class="xref py py-obj docutils literal"><span class="pre">InterfaceError</span></tt></a>
    |__ <a class="reference internal" href="#psycopg2.DatabaseError" title="psycopg2.DatabaseError"><tt class="xref py py-obj docutils literal"><span class="pre">DatabaseError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.DataError" title="psycopg2.DataError"><tt class="xref py py-obj docutils literal"><span class="pre">DataError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.OperationalError" title="psycopg2.OperationalError"><tt class="xref py py-obj docutils literal"><span class="pre">OperationalError</span></tt></a>
        |   |__ <a class="reference internal" href="extensions.html#psycopg2.extensions.QueryCanceledError" title="psycopg2.extensions.QueryCanceledError"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2.extensions.QueryCanceledError</span></tt></a>
        |   |__ <a class="reference internal" href="extensions.html#psycopg2.extensions.TransactionRollbackError" title="psycopg2.extensions.TransactionRollbackError"><tt class="xref py py-obj docutils literal"><span class="pre">psycopg2.extensions.TransactionRollbackError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.IntegrityError" title="psycopg2.IntegrityError"><tt class="xref py py-obj docutils literal"><span class="pre">IntegrityError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.InternalError" title="psycopg2.InternalError"><tt class="xref py py-obj docutils literal"><span class="pre">InternalError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.ProgrammingError" title="psycopg2.ProgrammingError"><tt class="xref py py-obj docutils literal"><span class="pre">ProgrammingError</span></tt></a>
        |__ <a class="reference internal" href="#psycopg2.NotSupportedError" title="psycopg2.NotSupportedError"><tt class="xref py py-obj docutils literal"><span class="pre">NotSupportedError</span></tt></a>
</pre>
</div>
<div class="section" id="type-objects-and-constructors">
<span id="id3"></span><h2>Type Objects and Constructors<a class="headerlink" href="#type-objects-and-constructors" title="Permalink to this headline"></a></h2>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">This section is mostly copied verbatim from the <a class="reference external" href="http://www.python.org/dev/peps/pep-0249/">DB API 2.0</a>
specification.  While these objects are exposed in compliance to the
DB API, Psycopg offers very accurate tools to convert data between Python
and PostgreSQL formats.  See <a class="reference internal" href="advanced.html#adapting-new-types"><em>Adapting new Python types to SQL syntax</em></a> and
<a class="reference internal" href="advanced.html#type-casting-from-sql-to-python"><em>Type casting of SQL types into Python objects</em></a></p>
</div>
<p>Many databases need to have the input in a particular format for
binding to an operation&#8217;s input parameters.  For example, if an
input is destined for a DATE column, then it must be bound to the
database in a particular string format.  Similar problems exist
for &#8220;Row ID&#8221; columns or large binary items (e.g. blobs or RAW
columns).  This presents problems for Python since the parameters
to the .execute*() method are untyped.  When the database module
sees a Python string object, it doesn&#8217;t know if it should be bound
as a simple CHAR column, as a raw BINARY item, or as a DATE.</p>
<p>To overcome this problem, a module must provide the constructors
defined below to create objects that can hold special values.
When passed to the cursor methods, the module can then detect the
proper type of the input parameter and bind it accordingly.</p>
<p>A Cursor Object&#8217;s description attribute returns information about
each of the result columns of a query.  The type_code must compare
equal to one of Type Objects defined below. Type Objects may be
equal to more than one type code (e.g. DATETIME could be equal to
the type codes for date, time and timestamp columns; see the
Implementation Hints below for details).</p>
<p>The module exports the following constructors and singletons:</p>
<dl class="function">
<dt id="psycopg2.Date">
<tt class="descclassname">psycopg2.</tt><tt class="descname">Date</tt><big>(</big><em>year</em>, <em>month</em>, <em>day</em><big>)</big><a class="headerlink" href="#psycopg2.Date" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a date value.</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.Time">
<tt class="descclassname">psycopg2.</tt><tt class="descname">Time</tt><big>(</big><em>hour</em>, <em>minute</em>, <em>second</em><big>)</big><a class="headerlink" href="#psycopg2.Time" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a time value.</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.Timestamp">
<tt class="descclassname">psycopg2.</tt><tt class="descname">Timestamp</tt><big>(</big><em>year</em>, <em>month</em>, <em>day</em>, <em>hour</em>, <em>minute</em>, <em>second</em><big>)</big><a class="headerlink" href="#psycopg2.Timestamp" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a time stamp value.</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.DateFromTicks">
<tt class="descclassname">psycopg2.</tt><tt class="descname">DateFromTicks</tt><big>(</big><em>ticks</em><big>)</big><a class="headerlink" href="#psycopg2.DateFromTicks" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a date value from the given
ticks value (number of seconds since the epoch; see the documentation of
the standard Python time module for details).</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.TimeFromTicks">
<tt class="descclassname">psycopg2.</tt><tt class="descname">TimeFromTicks</tt><big>(</big><em>ticks</em><big>)</big><a class="headerlink" href="#psycopg2.TimeFromTicks" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a time value from the given
ticks value (number of seconds since the epoch; see the documentation of
the standard Python time module for details).</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.TimestampFromTicks">
<tt class="descclassname">psycopg2.</tt><tt class="descname">TimestampFromTicks</tt><big>(</big><em>ticks</em><big>)</big><a class="headerlink" href="#psycopg2.TimestampFromTicks" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object holding a time stamp value from the
given ticks value (number of seconds since the epoch; see the
documentation of the standard Python time module for details).</p>
</dd></dl>

<dl class="function">
<dt id="psycopg2.Binary">
<tt class="descclassname">psycopg2.</tt><tt class="descname">Binary</tt><big>(</big><em>string</em><big>)</big><a class="headerlink" href="#psycopg2.Binary" title="Permalink to this definition"></a></dt>
<dd><p>This function constructs an object capable of holding a binary (long)
string value.</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.STRING">
<tt class="descclassname">psycopg2.</tt><tt class="descname">STRING</tt><a class="headerlink" href="#psycopg2.STRING" title="Permalink to this definition"></a></dt>
<dd><p>This type object is used to describe columns in a database that are
string-based (e.g. CHAR).</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.BINARY">
<tt class="descclassname">psycopg2.</tt><tt class="descname">BINARY</tt><a class="headerlink" href="#psycopg2.BINARY" title="Permalink to this definition"></a></dt>
<dd><p>This type object is used to describe (long) binary columns in a database
(e.g. LONG, RAW, BLOBs).</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.NUMBER">
<tt class="descclassname">psycopg2.</tt><tt class="descname">NUMBER</tt><a class="headerlink" href="#psycopg2.NUMBER" title="Permalink to this definition"></a></dt>
<dd><p>This type object is used to describe numeric columns in a database.</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.DATETIME">
<tt class="descclassname">psycopg2.</tt><tt class="descname">DATETIME</tt><a class="headerlink" href="#psycopg2.DATETIME" title="Permalink to this definition"></a></dt>
<dd><p>This type object is used to describe date/time columns in a database.</p>
</dd></dl>

<dl class="data">
<dt id="psycopg2.ROWID">
<tt class="descclassname">psycopg2.</tt><tt class="descname">ROWID</tt><a class="headerlink" href="#psycopg2.ROWID" title="Permalink to this definition"></a></dt>
<dd><p>This type object is used to describe the &#8220;Row ID&#8221; column in a database.</p>
</dd></dl>

</div>
</div>


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