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 <div class="section" id="module-sqlite3">
<h1>11.13. <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> — DB-API 2.0 interface for SQLite databases<a class="headerlink" href="#module-sqlite3" title="Permalink to this headline">¶</a></h1>
<div class="versionadded">
New in version 2.5.
</div>
SQLite is a C library that provides a lightweight disk-based database that
doesn’t require a separate server process and allows accessing the database
using a nonstandard variant of the SQL query language. Some applications can use
SQLite for internal data storage. It’s also possible to prototype an
application using SQLite and then port the code to a larger database such as
PostgreSQL or Oracle.
The sqlite3 module was written by Gerhard Häring. It provides a SQL interface
compliant with the DB-API 2.0 specification described by <a class="pep reference external" href="https://www.python.org/dev/peps/pep-0249">PEP 249</a>.
To use the module, you must first create a <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> object that
represents the database. Here the data will be stored in the
<code class="file docutils literal notranslate">example.db</code> file:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
conn = sqlite3.connect(&#39;example.db&#39;)
</pre></div>
</div>
You can also supply the special name <code class="docutils literal notranslate">:memory:</code> to create a database in RAM.
Once you have a <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a>, you can create a <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> object
and call its <a class="reference internal" href="#sqlite3.Cursor.execute" title="sqlite3.Cursor.execute"><code class="xref py py-meth docutils literal notranslate">execute()</code></a> method to perform SQL commands:
<div class="highlight-default notranslate"><div class="highlight"><pre>c = conn.cursor()

# Create table
c.execute(&#39;&#39;&#39;CREATE TABLE stocks
 (date text, trans text, symbol text, qty real, price real)&#39;&#39;&#39;)

# Insert a row of data
c.execute(&quot;INSERT INTO stocks VALUES (&#39;2006-01-05&#39;,&#39;BUY&#39;,&#39;RHAT&#39;,100,35.14)&quot;)

# Save (commit) the changes
conn.commit()

# We can also close the connection if we are done with it.
# Just be sure any changes have been committed or they will be lost.
conn.close()
</pre></div>
</div>
The data you’ve saved is persistent and is available in subsequent sessions:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
conn = sqlite3.connect(&#39;example.db&#39;)
c = conn.cursor()
</pre></div>
</div>
Usually your SQL operations will need to use values from Python variables. You
shouldn’t assemble your query using Python’s string operations because doing so
is insecure; it makes your program vulnerable to an SQL injection attack
(see <a class="reference external" href="https://xkcd.com/327/">https://xkcd.com/327/</a> for humorous example of what can go wrong).
Instead, use the DB-API’s parameter substitution. Put <code class="docutils literal notranslate">?</code> as a placeholder
wherever you want to use a value, and then provide a tuple of values as the
second argument to the cursor’s <a class="reference internal" href="#sqlite3.Cursor.execute" title="sqlite3.Cursor.execute"><code class="xref py py-meth docutils literal notranslate">execute()</code></a> method. (Other database
modules may use a different placeholder, such as <code class="docutils literal notranslate">%s</code> or <code class="docutils literal notranslate">:1</code>.) For
example:
<div class="highlight-default notranslate"><div class="highlight"><pre># Never do this -- insecure!
symbol = &#39;RHAT&#39;
c.execute(&quot;SELECT * FROM stocks WHERE symbol = &#39;%s&#39;&quot; % symbol)

# Do this instead
t = (&#39;RHAT&#39;,)
c.execute(&#39;SELECT * FROM stocks WHERE symbol=?&#39;, t)
print c.fetchone()

# Larger example that inserts many records at a time
purchases = [(&#39;2006-03-28&#39;, &#39;BUY&#39;, &#39;IBM&#39;, 1000, 45.00),
 (&#39;2006-04-05&#39;, &#39;BUY&#39;, &#39;MSFT&#39;, 1000, 72.00),
 (&#39;2006-04-06&#39;, &#39;SELL&#39;, &#39;IBM&#39;, 500, 53.00),
 ]
c.executemany(&#39;INSERT INTO stocks VALUES (?,?,?,?,?)&#39;, purchases)
</pre></div>
</div>
To retrieve data after executing a SELECT statement, you can either treat the
cursor as an <a class="reference internal" href="../glossary.html#term-iterator">iterator</a>, call the cursor’s <a class="reference internal" href="#sqlite3.Cursor.fetchone" title="sqlite3.Cursor.fetchone"><code class="xref py py-meth docutils literal notranslate">fetchone()</code></a> method to
retrieve a single matching row, or call <a class="reference internal" href="#sqlite3.Cursor.fetchall" title="sqlite3.Cursor.fetchall"><code class="xref py py-meth docutils literal notranslate">fetchall()</code></a> to get a list of the
matching rows.
This example uses the iterator form:
<div class="highlight-default notranslate"><div class="highlight"><pre>&gt;&gt;&gt; for row in c.execute(&#39;SELECT * FROM stocks ORDER BY price&#39;):
 print row

(u&#39;2006-01-05&#39;, u&#39;BUY&#39;, u&#39;RHAT&#39;, 100, 35.14)
(u&#39;2006-03-28&#39;, u&#39;BUY&#39;, u&#39;IBM&#39;, 1000, 45.0)
(u&#39;2006-04-06&#39;, u&#39;SELL&#39;, u&#39;IBM&#39;, 500, 53.0)
(u&#39;2006-04-05&#39;, u&#39;BUY&#39;, u&#39;MSFT&#39;, 1000, 72.0)
</pre></div>
</div>
<div class="admonition seealso">
See also
<dl class="last docutils">
<dt><a class="reference external" href="https://github.com/ghaering/pysqlite">https://github.com/ghaering/pysqlite</a></dt>
<dd>The pysqlite web page – sqlite3 is developed externally under the name
“pysqlite”.</dd>
<dt><a class="reference external" href="https://www.sqlite.org">https://www.sqlite.org</a></dt>
<dd>The SQLite web page; the documentation describes the syntax and the
available data types for the supported SQL dialect.</dd>
<dt><a class="reference external" href="http://www.w3schools.com/sql/">http://www.w3schools.com/sql/</a></dt>
<dd>Tutorial, reference and examples for learning SQL syntax.</dd>
<dt><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0249">PEP 249</a> - Database API Specification 2.0</dt>
<dd>PEP written by Marc-André Lemburg.</dd>
</dl>
</div>
<div class="section" id="module-functions-and-constants">
<h2>11.13.1. Module functions and constants<a class="headerlink" href="#module-functions-and-constants" title="Permalink to this headline">¶</a></h2>
<dl class="data">
<dt id="sqlite3.version">
<code class="descclassname">sqlite3.</code><code class="descname">version</code><a class="headerlink" href="#sqlite3.version" title="Permalink to this definition">¶</a></dt>
<dd>The version number of this module, as a string. This is not the version of
the SQLite library.
</dd></dl>

<dl class="data">
<dt id="sqlite3.version_info">
<code class="descclassname">sqlite3.</code><code class="descname">version_info</code><a class="headerlink" href="#sqlite3.version_info" title="Permalink to this definition">¶</a></dt>
<dd>The version number of this module, as a tuple of integers. This is not the
version of the SQLite library.
</dd></dl>

<dl class="data">
<dt id="sqlite3.sqlite_version">
<code class="descclassname">sqlite3.</code><code class="descname">sqlite_version</code><a class="headerlink" href="#sqlite3.sqlite_version" title="Permalink to this definition">¶</a></dt>
<dd>The version number of the run-time SQLite library, as a string.
</dd></dl>

<dl class="data">
<dt id="sqlite3.sqlite_version_info">
<code class="descclassname">sqlite3.</code><code class="descname">sqlite_version_info</code><a class="headerlink" href="#sqlite3.sqlite_version_info" title="Permalink to this definition">¶</a></dt>
<dd>The version number of the run-time SQLite library, as a tuple of integers.
</dd></dl>

<dl class="data">
<dt id="sqlite3.PARSE_DECLTYPES">
<code class="descclassname">sqlite3.</code><code class="descname">PARSE_DECLTYPES</code><a class="headerlink" href="#sqlite3.PARSE_DECLTYPES" title="Permalink to this definition">¶</a></dt>
<dd>This constant is meant to be used with the detect_types parameter of the
<a class="reference internal" href="#sqlite3.connect" title="sqlite3.connect"><code class="xref py py-func docutils literal notranslate">connect()</code></a> function.
Setting it makes the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module parse the declared type for each
column it returns. It will parse out the first word of the declared type,
i. e. for “integer primary key”, it will parse out “integer”, or for
“number(10)” it will parse out “number”. Then for that column, it will look
into the converters dictionary and use the converter function registered for
that type there.
</dd></dl>

<dl class="data">
<dt id="sqlite3.PARSE_COLNAMES">
<code class="descclassname">sqlite3.</code><code class="descname">PARSE_COLNAMES</code><a class="headerlink" href="#sqlite3.PARSE_COLNAMES" title="Permalink to this definition">¶</a></dt>
<dd>This constant is meant to be used with the detect_types parameter of the
<a class="reference internal" href="#sqlite3.connect" title="sqlite3.connect"><code class="xref py py-func docutils literal notranslate">connect()</code></a> function.
Setting this makes the SQLite interface parse the column name for each column it
returns. It will look for a string formed [mytype] in there, and then decide
that ‘mytype’ is the type of the column. It will try to find an entry of
‘mytype’ in the converters dictionary and then use the converter function found
there to return the value. The column name found in <a class="reference internal" href="#sqlite3.Cursor.description" title="sqlite3.Cursor.description"><code class="xref py py-attr docutils literal notranslate">Cursor.description</code></a>
is only the first word of the column name, i. e. if you use something like
<code class="docutils literal notranslate">'as &quot;x [datetime]&quot;'</code> in your SQL, then we will parse out everything until the
first blank for the column name: the column name would simply be “x”.
</dd></dl>

<dl class="function">
<dt id="sqlite3.connect">
<code class="descclassname">sqlite3.</code><code class="descname">connect</code>(database[, timeout, detect_types, isolation_level, check_same_thread, factory, cached_statements])<a class="headerlink" href="#sqlite3.connect" title="Permalink to this definition">¶</a></dt>
<dd>Opens a connection to the SQLite database file database. You can use
<code class="docutils literal notranslate">&quot;:memory:&quot;</code> to open a database connection to a database that resides in RAM
instead of on disk.
When a database is accessed by multiple connections, and one of the processes
modifies the database, the SQLite database is locked until that transaction is
committed. The timeout parameter specifies how long the connection should wait
for the lock to go away until raising an exception. The default for the timeout
parameter is 5.0 (five seconds).
For the isolation_level parameter, please see the
<a class="reference internal" href="#sqlite3.Connection.isolation_level" title="sqlite3.Connection.isolation_level"><code class="xref py py-attr docutils literal notranslate">Connection.isolation_level</code></a> property of <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> objects.
SQLite natively supports only the types TEXT, INTEGER, REAL, BLOB and NULL. If
you want to use other types you must add support for them yourself. The
detect_types parameter and the using custom converters registered with the
module-level <a class="reference internal" href="#sqlite3.register_converter" title="sqlite3.register_converter"><code class="xref py py-func docutils literal notranslate">register_converter()</code></a> function allow you to easily do that.
detect_types defaults to 0 (i. e. off, no type detection), you can set it to
any combination of <a class="reference internal" href="#sqlite3.PARSE_DECLTYPES" title="sqlite3.PARSE_DECLTYPES"><code class="xref py py-const docutils literal notranslate">PARSE_DECLTYPES</code></a> and <a class="reference internal" href="#sqlite3.PARSE_COLNAMES" title="sqlite3.PARSE_COLNAMES"><code class="xref py py-const docutils literal notranslate">PARSE_COLNAMES</code></a> to turn
type detection on.
By default, the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module uses its <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> class for the
connect call. You can, however, subclass the <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> class and make
<a class="reference internal" href="#sqlite3.connect" title="sqlite3.connect"><code class="xref py py-func docutils literal notranslate">connect()</code></a> use your class instead by providing your class for the factory
parameter.
Consult the section <a class="reference internal" href="#sqlite3-types">SQLite and Python types</a> of this manual for details.
The <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module internally uses a statement cache to avoid SQL parsing
overhead. If you want to explicitly set the number of statements that are cached
for the connection, you can set the cached_statements parameter. The currently
implemented default is to cache 100 statements.
</dd></dl>

<dl class="function">
<dt id="sqlite3.register_converter">
<code class="descclassname">sqlite3.</code><code class="descname">register_converter</code>(typename, callable)<a class="headerlink" href="#sqlite3.register_converter" title="Permalink to this definition">¶</a></dt>
<dd>Registers a callable to convert a bytestring from the database into a custom
Python type. The callable will be invoked for all database values that are of
the type typename. Confer the parameter detect_types of the <a class="reference internal" href="#sqlite3.connect" title="sqlite3.connect"><code class="xref py py-func docutils literal notranslate">connect()</code></a>
function for how the type detection works. Note that typename and the name of
the type in your query are matched in case-insensitive manner.
</dd></dl>

<dl class="function">
<dt id="sqlite3.register_adapter">
<code class="descclassname">sqlite3.</code><code class="descname">register_adapter</code>(type, callable)<a class="headerlink" href="#sqlite3.register_adapter" title="Permalink to this definition">¶</a></dt>
<dd>Registers a callable to convert the custom Python type type into one of
SQLite’s supported types. The callable callable accepts as single parameter
the Python value, and must return a value of the following types: int, long,
float, str (UTF-8 encoded), unicode or buffer.
</dd></dl>

<dl class="function">
<dt id="sqlite3.complete_statement">
<code class="descclassname">sqlite3.</code><code class="descname">complete_statement</code>(sql)<a class="headerlink" href="#sqlite3.complete_statement" title="Permalink to this definition">¶</a></dt>
<dd>Returns <a class="reference internal" href="constants.html#True" title="True"><code class="xref py py-const docutils literal notranslate">True</code></a> if the string sql contains one or more complete SQL
statements terminated by semicolons. It does not verify that the SQL is
syntactically correct, only that there are no unclosed string literals and the
statement is terminated by a semicolon.
This can be used to build a shell for SQLite, as in the following example:
<div class="highlight-default notranslate"><div class="highlight"><pre># A minimal SQLite shell for experiments

import sqlite3

buffer = &quot;&quot;

print &quot;Enter your SQL commands to execute in sqlite3.&quot;
print &quot;Enter a blank line to exit.&quot;

while True:
 line = raw_input()
 if line == &quot;&quot;:
 break
 buffer += line
 if sqlite3.complete_statement(buffer):
 try:
 buffer = buffer.strip()
 cur.execute(buffer)

if buffer.lstrip().upper().startswith(&quot;SELECT&quot;):
 print cur.fetchall()
 except sqlite3.Error as e:
 print &quot;An error occurred:&quot;, e.args[0]
 buffer = &quot;&quot;

con.close()
</pre></div>
</div>
</dd></dl>

<dl class="function">
<dt id="sqlite3.enable_callback_tracebacks">
<code class="descclassname">sqlite3.</code><code class="descname">enable_callback_tracebacks</code>(flag)<a class="headerlink" href="#sqlite3.enable_callback_tracebacks" title="Permalink to this definition">¶</a></dt>
<dd>By default you will not get any tracebacks in user-defined functions,
aggregates, converters, authorizer callbacks etc. If you want to debug them,
you can call this function with flag set to <code class="docutils literal notranslate">True</code>. Afterwards, you will
get tracebacks from callbacks on <code class="docutils literal notranslate">sys.stderr</code>. Use <a class="reference internal" href="constants.html#False" title="False"><code class="xref py py-const docutils literal notranslate">False</code></a> to
disable the feature again.
</dd></dl>

</div>
<div class="section" id="connection-objects">
<h2>11.13.2. Connection Objects<a class="headerlink" href="#connection-objects" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="sqlite3.Connection">
class <code class="descclassname">sqlite3.</code><code class="descname">Connection</code><a class="headerlink" href="#sqlite3.Connection" title="Permalink to this definition">¶</a></dt>
<dd>A SQLite database connection has the following attributes and methods:
<dl class="attribute">
<dt id="sqlite3.Connection.isolation_level">
<code class="descname">isolation_level</code><a class="headerlink" href="#sqlite3.Connection.isolation_level" title="Permalink to this definition">¶</a></dt>
<dd>Get or set the current isolation level. <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a> for autocommit mode or
one of “DEFERRED”, “IMMEDIATE” or “EXCLUSIVE”. See section
<a class="reference internal" href="#sqlite3-controlling-transactions">Controlling Transactions</a> for a more detailed explanation.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.cursor">
<code class="descname">cursor</code>(factory=Cursor)<a class="headerlink" href="#sqlite3.Connection.cursor" title="Permalink to this definition">¶</a></dt>
<dd>The cursor method accepts a single optional parameter factory. If
supplied, this must be a callable returning an instance of <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a>
or its subclasses.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.commit">
<code class="descname">commit</code>()<a class="headerlink" href="#sqlite3.Connection.commit" title="Permalink to this definition">¶</a></dt>
<dd>This method commits the current transaction. If you don’t call this method,
anything you did since the last call to <code class="docutils literal notranslate">commit()</code> is not visible from
other database connections. If you wonder why you don’t see the data you’ve
written to the database, please check you didn’t forget to call this method.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.rollback">
<code class="descname">rollback</code>()<a class="headerlink" href="#sqlite3.Connection.rollback" title="Permalink to this definition">¶</a></dt>
<dd>This method rolls back any changes to the database since the last call to
<a class="reference internal" href="#sqlite3.Connection.commit" title="sqlite3.Connection.commit"><code class="xref py py-meth docutils literal notranslate">commit()</code></a>.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.close">
<code class="descname">close</code>()<a class="headerlink" href="#sqlite3.Connection.close" title="Permalink to this definition">¶</a></dt>
<dd>This closes the database connection. Note that this does not automatically
call <a class="reference internal" href="#sqlite3.Connection.commit" title="sqlite3.Connection.commit"><code class="xref py py-meth docutils literal notranslate">commit()</code></a>. If you just close your database connection without
calling <a class="reference internal" href="#sqlite3.Connection.commit" title="sqlite3.Connection.commit"><code class="xref py py-meth docutils literal notranslate">commit()</code></a> first, your changes will be lost!
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.execute">
<code class="descname">execute</code>(sql[, parameters])<a class="headerlink" href="#sqlite3.Connection.execute" title="Permalink to this definition">¶</a></dt>
<dd>This is a nonstandard shortcut that creates an intermediate cursor object by
calling the cursor method, then calls the cursor’s <a class="reference internal" href="#sqlite3.Cursor.execute" title="sqlite3.Cursor.execute"><code class="xref py py-meth docutils literal notranslate">execute</code></a> method with the parameters given.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.executemany">
<code class="descname">executemany</code>(sql[, parameters])<a class="headerlink" href="#sqlite3.Connection.executemany" title="Permalink to this definition">¶</a></dt>
<dd>This is a nonstandard shortcut that creates an intermediate cursor object by
calling the cursor method, then calls the cursor’s <a class="reference internal" href="#sqlite3.Cursor.executemany" title="sqlite3.Cursor.executemany"><code class="xref py py-meth docutils literal notranslate">executemany</code></a> method with the parameters given.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.executescript">
<code class="descname">executescript</code>(sql_script)<a class="headerlink" href="#sqlite3.Connection.executescript" title="Permalink to this definition">¶</a></dt>
<dd>This is a nonstandard shortcut that creates an intermediate cursor object by
calling the cursor method, then calls the cursor’s <a class="reference internal" href="#sqlite3.Cursor.executescript" title="sqlite3.Cursor.executescript"><code class="xref py py-meth docutils literal notranslate">executescript</code></a> method with the parameters given.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.create_function">
<code class="descname">create_function</code>(name, num_params, func)<a class="headerlink" href="#sqlite3.Connection.create_function" title="Permalink to this definition">¶</a></dt>
<dd>Creates a user-defined function that you can later use from within SQL
statements under the function name name. num_params is the number of
parameters the function accepts, and func is a Python callable that is called
as the SQL function.
The function can return any of the types supported by SQLite: unicode, str, int,
long, float, buffer and <code class="docutils literal notranslate">None</code>.
Example:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
import md5

def md5sum(t):
 return md5.md5(t).hexdigest()

<dl class="method">
<dt id="sqlite3.Connection.create_aggregate">
<code class="descname">create_aggregate</code>(name, num_params, aggregate_class)<a class="headerlink" href="#sqlite3.Connection.create_aggregate" title="Permalink to this definition">¶</a></dt>
<dd>Creates a user-defined aggregate function.
The aggregate class must implement a <code class="docutils literal notranslate">step</code> method, which accepts the number
of parameters num_params, and a <code class="docutils literal notranslate">finalize</code> method which will return the
final result of the aggregate.
The <code class="docutils literal notranslate">finalize</code> method can return any of the types supported by SQLite:
unicode, str, int, long, float, buffer and <code class="docutils literal notranslate">None</code>.
Example:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

class MySum:
 def __init__(self):
 self.count = 0

def step(self, value):
 self.count += value

def finalize(self):
 return self.count

con = sqlite3.connect(&quot;:memory:&quot;)
con.create_aggregate(&quot;mysum&quot;, 1, MySum)
cur = con.cursor()
cur.execute(&quot;create table test(i)&quot;)
cur.execute(&quot;insert into test(i) values (1)&quot;)
cur.execute(&quot;insert into test(i) values (2)&quot;)
cur.execute(&quot;select mysum(i) from test&quot;)
print cur.fetchone()[0]
</pre></div>
</div>
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.create_collation">
<code class="descname">create_collation</code>(name, callable)<a class="headerlink" href="#sqlite3.Connection.create_collation" title="Permalink to this definition">¶</a></dt>
<dd>Creates a collation with the specified name and callable. The callable will
be passed two string arguments. It should return -1 if the first is ordered
lower than the second, 0 if they are ordered equal and 1 if the first is ordered
higher than the second. Note that this controls sorting (ORDER BY in SQL) so
your comparisons don’t affect other SQL operations.
Note that the callable will get its parameters as Python bytestrings, which will
normally be encoded in UTF-8.
The following example shows a custom collation that sorts “the wrong way”:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

def collate_reverse(string1, string2):
 return -cmp(string1, string2)

cur = con.cursor()
cur.execute(&quot;create table test(x)&quot;)
cur.executemany(&quot;insert into test(x) values (?)&quot;, [(&quot;a&quot;,), (&quot;b&quot;,)])
cur.execute(&quot;select x from test order by x collate reverse&quot;)
for row in cur:
 print row
con.close()
</pre></div>
</div>
To remove a collation, call <code class="docutils literal notranslate">create_collation</code> with <code class="docutils literal notranslate">None</code> as callable:
<div class="highlight-default notranslate"><div class="highlight"><pre>con.create_collation(&quot;reverse&quot;, None)
</pre></div>
</div>
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.interrupt">
<code class="descname">interrupt</code>()<a class="headerlink" href="#sqlite3.Connection.interrupt" title="Permalink to this definition">¶</a></dt>
<dd>You can call this method from a different thread to abort any queries that might
be executing on the connection. The query will then abort and the caller will
get an exception.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.set_authorizer">
<code class="descname">set_authorizer</code>(authorizer_callback)<a class="headerlink" href="#sqlite3.Connection.set_authorizer" title="Permalink to this definition">¶</a></dt>
<dd>This routine registers a callback. The callback is invoked for each attempt to
access a column of a table in the database. The callback should return
<code class="xref py py-const docutils literal notranslate">SQLITE_OK</code> if access is allowed, <code class="xref py py-const docutils literal notranslate">SQLITE_DENY</code> if the entire SQL
statement should be aborted with an error and <code class="xref py py-const docutils literal notranslate">SQLITE_IGNORE</code> if the
column should be treated as a NULL value. These constants are available in the
<a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module.
The first argument to the callback signifies what kind of operation is to be
authorized. The second and third argument will be arguments or <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a>
depending on the first argument. The 4th argument is the name of the database
(“main”, “temp”, etc.) if applicable. The 5th argument is the name of the
inner-most trigger or view that is responsible for the access attempt or
<a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a> if this access attempt is directly from input SQL code.
Please consult the SQLite documentation about the possible values for the first
argument and the meaning of the second and third argument depending on the first
one. All necessary constants are available in the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.set_progress_handler">
<code class="descname">set_progress_handler</code>(handler, n)<a class="headerlink" href="#sqlite3.Connection.set_progress_handler" title="Permalink to this definition">¶</a></dt>
<dd>This routine registers a callback. The callback is invoked for every n
instructions of the SQLite virtual machine. This is useful if you want to
get called from SQLite during long-running operations, for example to update
a GUI.
If you want to clear any previously installed progress handler, call the
method with <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a> for handler.
<div class="versionadded">
New in version 2.6.
</div>
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.enable_load_extension">
<code class="descname">enable_load_extension</code>(enabled)<a class="headerlink" href="#sqlite3.Connection.enable_load_extension" title="Permalink to this definition">¶</a></dt>
<dd>This routine allows/disallows the SQLite engine to load SQLite extensions
from shared libraries. SQLite extensions can define new functions,
aggregates or whole new virtual table implementations. One well-known
extension is the fulltext-search extension distributed with SQLite.
Loadable extensions are disabled by default. See <a class="footnote-reference" href="#f1" id="id1">[1]</a>.
<div class="versionadded">
New in version 2.7.
</div>
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

# enable extension loading
con.enable_load_extension(True)

# Load the fulltext search extension
con.execute(&quot;select load_extension(&#39;./fts3.so&#39;)&quot;)

# alternatively you can load the extension using an API call:
# con.load_extension(&quot;./fts3.so&quot;)

# disable extension loading again
con.enable_load_extension(False)

# example from SQLite wiki
con.execute(&quot;create virtual table recipe using fts3(name, ingredients)&quot;)
con.executescript(&quot;&quot;&quot;
 insert into recipe (name, ingredients) values (&#39;broccoli stew&#39;, &#39;broccoli peppers cheese tomatoes&#39;);
 insert into recipe (name, ingredients) values (&#39;pumpkin stew&#39;, &#39;pumpkin onions garlic celery&#39;);
 insert into recipe (name, ingredients) values (&#39;broccoli pie&#39;, &#39;broccoli cheese onions flour&#39;);
 insert into recipe (name, ingredients) values (&#39;pumpkin pie&#39;, &#39;pumpkin sugar flour butter&#39;);
 &quot;&quot;&quot;)
for row in con.execute(&quot;select rowid, name, ingredients from recipe where name match &#39;pie&#39;&quot;):
 print row
</pre></div>
</div>
</dd></dl>

<dl class="method">
<dt id="sqlite3.Connection.load_extension">
<code class="descname">load_extension</code>(path)<a class="headerlink" href="#sqlite3.Connection.load_extension" title="Permalink to this definition">¶</a></dt>
<dd>This routine loads a SQLite extension from a shared library. You have to
enable extension loading with <a class="reference internal" href="#sqlite3.Connection.enable_load_extension" title="sqlite3.Connection.enable_load_extension"><code class="xref py py-meth docutils literal notranslate">enable_load_extension()</code></a> before you can
use this routine.
Loadable extensions are disabled by default. See <a class="footnote-reference" href="#f1" id="id2">[1]</a>.
<div class="versionadded">
New in version 2.7.
</div>
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Connection.row_factory">
<code class="descname">row_factory</code><a class="headerlink" href="#sqlite3.Connection.row_factory" title="Permalink to this definition">¶</a></dt>
<dd>You can change this attribute to a callable that accepts the cursor and the
original row as a tuple and will return the real result row. This way, you can
implement more advanced ways of returning results, such as returning an object
that can also access columns by name.
Example:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

def dict_factory(cursor, row):
 d = {}
 for idx, col in enumerate(cursor.description):
 d[col[0]] = row[idx]
 return d

con = sqlite3.connect(&quot;:memory:&quot;)
con.row_factory = dict_factory
cur = con.cursor()
cur.execute(&quot;select 1 as a&quot;)
print cur.fetchone()[&quot;a&quot;]
</pre></div>
</div>
If returning a tuple doesn’t suffice and you want name-based access to
columns, you should consider setting <a class="reference internal" href="#sqlite3.Connection.row_factory" title="sqlite3.Connection.row_factory"><code class="xref py py-attr docutils literal notranslate">row_factory</code></a> to the
highly-optimized <a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">sqlite3.Row</code></a> type. <a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">Row</code></a> provides both
index-based and case-insensitive name-based access to columns with almost no
memory overhead. It will probably be better than your own custom
dictionary-based approach or even a db_row based solution.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Connection.text_factory">
<code class="descname">text_factory</code><a class="headerlink" href="#sqlite3.Connection.text_factory" title="Permalink to this definition">¶</a></dt>
<dd>Using this attribute you can control what objects are returned for the <code class="docutils literal notranslate">TEXT</code>
data type. By default, this attribute is set to <a class="reference internal" href="functions.html#unicode" title="unicode"><code class="xref py py-class docutils literal notranslate">unicode</code></a> and the
<a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module will return Unicode objects for <code class="docutils literal notranslate">TEXT</code>. If you want to
return bytestrings instead, you can set it to <a class="reference internal" href="functions.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>.
For efficiency reasons, there’s also a way to return Unicode objects only for
non-ASCII data, and bytestrings otherwise. To activate it, set this attribute to
<code class="xref py py-const docutils literal notranslate">sqlite3.OptimizedUnicode</code>.
You can also set it to any other callable that accepts a single bytestring
parameter and returns the resulting object.
See the following example code for illustration:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

AUSTRIA = u&quot;\xd6sterreich&quot;

# by default, rows are returned as Unicode
cur.execute(&quot;select ?&quot;, (AUSTRIA,))
row = cur.fetchone()
assert row[0] == AUSTRIA

# but we can make sqlite3 always return bytestrings ...
con.text_factory = str
cur.execute(&quot;select ?&quot;, (AUSTRIA,))
row = cur.fetchone()
assert type(row[0]) is str
# the bytestrings will be encoded in UTF-8, unless you stored garbage in the
# database ...
assert row[0] == AUSTRIA.encode(&quot;utf-8&quot;)

# we can also implement a custom text_factory ...
# here we implement one that will ignore Unicode characters that cannot be
# decoded from UTF-8
con.text_factory = lambda x: unicode(x, &quot;utf-8&quot;, &quot;ignore&quot;)
cur.execute(&quot;select ?&quot;, (&quot;this is latin1 and would normally create errors&quot; +
 u&quot;\xe4\xf6\xfc&quot;.encode(&quot;latin1&quot;),))
row = cur.fetchone()
assert type(row[0]) is unicode

# sqlite3 offers a built-in optimized text_factory that will return bytestring
# objects, if the data is in ASCII only, and otherwise return unicode objects
con.text_factory = sqlite3.OptimizedUnicode
cur.execute(&quot;select ?&quot;, (AUSTRIA,))
row = cur.fetchone()
assert type(row[0]) is unicode

cur.execute(&quot;select ?&quot;, (&quot;Germany&quot;,))
row = cur.fetchone()
assert type(row[0]) is str
</pre></div>
</div>
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Connection.total_changes">
<code class="descname">total_changes</code><a class="headerlink" href="#sqlite3.Connection.total_changes" title="Permalink to this definition">¶</a></dt>
<dd>Returns the total number of database rows that have been modified, inserted, or
deleted since the database connection was opened.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Connection.iterdump">
<code class="descname">iterdump</code><a class="headerlink" href="#sqlite3.Connection.iterdump" title="Permalink to this definition">¶</a></dt>
<dd>Returns an iterator to dump the database in an SQL text format. Useful when
saving an in-memory database for later restoration. This function provides
the same capabilities as the <kbd class="kbd docutils literal notranslate">.dump</kbd> command in the sqlite3
shell.
<div class="versionadded">
New in version 2.6.
</div>
Example:
<div class="highlight-default notranslate"><div class="highlight"><pre># Convert file existing_db.db to SQL dump file dump.sql
import sqlite3, os

</dd></dl>

</div>
<div class="section" id="cursor-objects">
<h2>11.13.3. Cursor Objects<a class="headerlink" href="#cursor-objects" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="sqlite3.Cursor">
class <code class="descclassname">sqlite3.</code><code class="descname">Cursor</code><a class="headerlink" href="#sqlite3.Cursor" title="Permalink to this definition">¶</a></dt>
<dd>A <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> instance has the following attributes and methods.
<dl class="method">
<dt id="sqlite3.Cursor.execute">
<code class="descname">execute</code>(sql[, parameters])<a class="headerlink" href="#sqlite3.Cursor.execute" title="Permalink to this definition">¶</a></dt>
<dd>Executes an SQL statement. The SQL statement may be parameterized (i. e.
placeholders instead of SQL literals). The <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module supports two
kinds of placeholders: question marks (qmark style) and named placeholders
(named style).
Here’s an example of both styles:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

who = &quot;Yeltsin&quot;
age = 72

# This is the qmark style:
cur.execute(&quot;insert into people values (?, ?)&quot;, (who, age))

# And this is the named style:
cur.execute(&quot;select * from people where name_last=:who and age=:age&quot;, {&quot;who&quot;: who, &quot;age&quot;: age})

print cur.fetchone()
</pre></div>
</div>
<a class="reference internal" href="#sqlite3.Cursor.execute" title="sqlite3.Cursor.execute"><code class="xref py py-meth docutils literal notranslate">execute()</code></a> will only execute a single SQL statement. If you try to execute
more than one statement with it, it will raise a Warning. Use
<a class="reference internal" href="#sqlite3.Cursor.executescript" title="sqlite3.Cursor.executescript"><code class="xref py py-meth docutils literal notranslate">executescript()</code></a> if you want to execute multiple SQL statements with one
call.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Cursor.executemany">
<code class="descname">executemany</code>(sql, seq_of_parameters)<a class="headerlink" href="#sqlite3.Cursor.executemany" title="Permalink to this definition">¶</a></dt>
<dd>Executes an SQL command against all parameter sequences or mappings found in
the sequence sql. The <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module also allows using an
<a class="reference internal" href="../glossary.html#term-iterator">iterator</a> yielding parameters instead of a sequence.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

class IterChars:
 def __init__(self):
 self.count = ord(&#39;a&#39;)

def __iter__(self):
 return self

def next(self):
 if self.count &gt; ord(&#39;z&#39;):
 raise StopIteration
 self.count += 1
 return (chr(self.count - 1),) # this is a 1-tuple

theIter = IterChars()
cur.executemany(&quot;insert into characters(c) values (?)&quot;, theIter)

cur.execute(&quot;select c from characters&quot;)
print cur.fetchall()
</pre></div>
</div>
Here’s a shorter example using a <a class="reference internal" href="../glossary.html#term-generator">generator</a>:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
import string

def char_generator():
 for c in string.lowercase:
 yield (c,)

cur.executemany(&quot;insert into characters(c) values (?)&quot;, char_generator())

<dl class="method">
<dt id="sqlite3.Cursor.executescript">
<code class="descname">executescript</code>(sql_script)<a class="headerlink" href="#sqlite3.Cursor.executescript" title="Permalink to this definition">¶</a></dt>
<dd>This is a nonstandard convenience method for executing multiple SQL statements
at once. It issues a <code class="docutils literal notranslate">COMMIT</code> statement first, then executes the SQL script it
gets as a parameter.
sql_script can be a bytestring or a Unicode string.
Example:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

create table book(
 title,
 author,
 published
 );

insert into book(title, author, published)
 values (
 &#39;Dirk Gently&#39;&#39;s Holistic Detective Agency&#39;,
 &#39;Douglas Adams&#39;,
 1987
 );
 &quot;&quot;&quot;)
</pre></div>
</div>
</dd></dl>

<dl class="method">
<dt id="sqlite3.Cursor.fetchone">
<code class="descname">fetchone</code>()<a class="headerlink" href="#sqlite3.Cursor.fetchone" title="Permalink to this definition">¶</a></dt>
<dd>Fetches the next row of a query result set, returning a single sequence,
or <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a> when no more data is available.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Cursor.fetchmany">
<code class="descname">fetchmany</code>([size=cursor.arraysize])<a class="headerlink" href="#sqlite3.Cursor.fetchmany" title="Permalink to this definition">¶</a></dt>
<dd>Fetches the next set of rows of a query result, returning a list. An empty
list is returned when no more rows are available.
The number of rows to fetch per call is specified by the size parameter.
If it is not given, the cursor’s arraysize determines the number of rows
to be fetched. The method should try to fetch as many rows as indicated by
the size parameter. If this is not possible due to the specified number of
rows not being available, fewer rows may be returned.
Note there are performance considerations involved with the size parameter.
For optimal performance, it is usually best to use the arraysize attribute.
If the size parameter is used, then it is best for it to retain the same
value from one <a class="reference internal" href="#sqlite3.Cursor.fetchmany" title="sqlite3.Cursor.fetchmany"><code class="xref py py-meth docutils literal notranslate">fetchmany()</code></a> call to the next.
</dd></dl>

<dl class="method">
<dt id="sqlite3.Cursor.fetchall">
<code class="descname">fetchall</code>()<a class="headerlink" href="#sqlite3.Cursor.fetchall" title="Permalink to this definition">¶</a></dt>
<dd>Fetches all (remaining) rows of a query result, returning a list. Note that
the cursor’s arraysize attribute can affect the performance of this operation.
An empty list is returned when no rows are available.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Cursor.rowcount">
<code class="descname">rowcount</code><a class="headerlink" href="#sqlite3.Cursor.rowcount" title="Permalink to this definition">¶</a></dt>
<dd>Although the <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> class of the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module implements this
attribute, the database engine’s own support for the determination of “rows
affected”/”rows selected” is quirky.
For <a class="reference internal" href="#sqlite3.Cursor.executemany" title="sqlite3.Cursor.executemany"><code class="xref py py-meth docutils literal notranslate">executemany()</code></a> statements, the number of modifications are summed up
into <a class="reference internal" href="#sqlite3.Cursor.rowcount" title="sqlite3.Cursor.rowcount"><code class="xref py py-attr docutils literal notranslate">rowcount</code></a>.
As required by the Python DB API Spec, the <a class="reference internal" href="#sqlite3.Cursor.rowcount" title="sqlite3.Cursor.rowcount"><code class="xref py py-attr docutils literal notranslate">rowcount</code></a> attribute “is -1 in
case no <code class="docutils literal notranslate">executeXX()</code> has been performed on the cursor or the rowcount of the
last operation is not determinable by the interface”. This includes <code class="docutils literal notranslate">SELECT</code>
statements because we cannot determine the number of rows a query produced
until all rows were fetched.
With SQLite versions before 3.6.5, <a class="reference internal" href="#sqlite3.Cursor.rowcount" title="sqlite3.Cursor.rowcount"><code class="xref py py-attr docutils literal notranslate">rowcount</code></a> is set to 0 if
you make a <code class="docutils literal notranslate">DELETE FROM table</code> without any condition.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Cursor.lastrowid">
<code class="descname">lastrowid</code><a class="headerlink" href="#sqlite3.Cursor.lastrowid" title="Permalink to this definition">¶</a></dt>
<dd>This read-only attribute provides the rowid of the last modified row. It is
only set if you issued an <code class="docutils literal notranslate">INSERT</code> statement using the <a class="reference internal" href="#sqlite3.Cursor.execute" title="sqlite3.Cursor.execute"><code class="xref py py-meth docutils literal notranslate">execute()</code></a>
method. For operations other than <code class="docutils literal notranslate">INSERT</code> or when <a class="reference internal" href="#sqlite3.Cursor.executemany" title="sqlite3.Cursor.executemany"><code class="xref py py-meth docutils literal notranslate">executemany()</code></a> is
called, <a class="reference internal" href="#sqlite3.Cursor.lastrowid" title="sqlite3.Cursor.lastrowid"><code class="xref py py-attr docutils literal notranslate">lastrowid</code></a> is set to <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a>.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Cursor.description">
<code class="descname">description</code><a class="headerlink" href="#sqlite3.Cursor.description" title="Permalink to this definition">¶</a></dt>
<dd>This read-only attribute provides the column names of the last query. To
remain compatible with the Python DB API, it returns a 7-tuple for each
column where the last six items of each tuple are <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a>.
It is set for <code class="docutils literal notranslate">SELECT</code> statements without any matching rows as well.
</dd></dl>

<dl class="attribute">
<dt id="sqlite3.Cursor.connection">
<code class="descname">connection</code><a class="headerlink" href="#sqlite3.Cursor.connection" title="Permalink to this definition">¶</a></dt>
<dd>This read-only attribute provides the SQLite database <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a>
used by the <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> object. A <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> object created by
calling <a class="reference internal" href="#sqlite3.Connection.cursor" title="sqlite3.Connection.cursor"><code class="xref py py-meth docutils literal notranslate">con.cursor()</code></a> will have a
<a class="reference internal" href="#sqlite3.Cursor.connection" title="sqlite3.Cursor.connection"><code class="xref py py-attr docutils literal notranslate">connection</code></a> attribute that refers to con:
<div class="highlight-default notranslate"><div class="highlight"><pre>&gt;&gt;&gt; con = sqlite3.connect(&quot;:memory:&quot;)
&gt;&gt;&gt; cur = con.cursor()
&gt;&gt;&gt; cur.connection == con
True
</pre></div>
</div>
</dd></dl>

</dd></dl>

</div>
<div class="section" id="row-objects">
<h2>11.13.4. Row Objects<a class="headerlink" href="#row-objects" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="sqlite3.Row">
class <code class="descclassname">sqlite3.</code><code class="descname">Row</code><a class="headerlink" href="#sqlite3.Row" title="Permalink to this definition">¶</a></dt>
<dd>A <a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">Row</code></a> instance serves as a highly optimized
<a class="reference internal" href="#sqlite3.Connection.row_factory" title="sqlite3.Connection.row_factory"><code class="xref py py-attr docutils literal notranslate">row_factory</code></a> for <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> objects.
It tries to mimic a tuple in most of its features.
It supports mapping access by column name and index, iteration,
representation, equality testing and <a class="reference internal" href="functions.html#len" title="len"><code class="xref py py-func docutils literal notranslate">len()</code></a>.
If two <a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">Row</code></a> objects have exactly the same columns and their
members are equal, they compare equal.
<div class="versionchanged">
Changed in version 2.6: Added iteration and equality (hashability).
</div>
<dl class="method">
<dt id="sqlite3.Row.keys">
<code class="descname">keys</code>()<a class="headerlink" href="#sqlite3.Row.keys" title="Permalink to this definition">¶</a></dt>
<dd>This method returns a list of column names. Immediately after a query,
it is the first member of each tuple in <a class="reference internal" href="#sqlite3.Cursor.description" title="sqlite3.Cursor.description"><code class="xref py py-attr docutils literal notranslate">Cursor.description</code></a>.
<div class="versionadded">
New in version 2.6.
</div>
</dd></dl>

</dd></dl>

Let’s assume we initialize a table as in the example given above:
<div class="highlight-default notranslate"><div class="highlight"><pre>conn = sqlite3.connect(&quot;:memory:&quot;)
c = conn.cursor()
c.execute(&#39;&#39;&#39;create table stocks
(date text, trans text, symbol text,
 qty real, price real)&#39;&#39;&#39;)
c.execute(&quot;&quot;&quot;insert into stocks
 values (&#39;2006-01-05&#39;,&#39;BUY&#39;,&#39;RHAT&#39;,100,35.14)&quot;&quot;&quot;)
conn.commit()
c.close()
</pre></div>
</div>
Now we plug <a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">Row</code></a> in:
<div class="highlight-default notranslate"><div class="highlight"><pre>&gt;&gt;&gt; conn.row_factory = sqlite3.Row
&gt;&gt;&gt; c = conn.cursor()
&gt;&gt;&gt; c.execute(&#39;select * from stocks&#39;)
&lt;sqlite3.Cursor object at 0x7f4e7dd8fa80&gt;
&gt;&gt;&gt; r = c.fetchone()
&gt;&gt;&gt; type(r)
&lt;type &#39;sqlite3.Row&#39;&gt;
&gt;&gt;&gt; r
(u&#39;2006-01-05&#39;, u&#39;BUY&#39;, u&#39;RHAT&#39;, 100.0, 35.14)
&gt;&gt;&gt; len(r)
5
&gt;&gt;&gt; r[2]
u&#39;RHAT&#39;
&gt;&gt;&gt; r.keys()
[&#39;date&#39;, &#39;trans&#39;, &#39;symbol&#39;, &#39;qty&#39;, &#39;price&#39;]
&gt;&gt;&gt; r[&#39;qty&#39;]
100.0
&gt;&gt;&gt; for member in r:
... print member
...
2006-01-05
BUY
RHAT
100.0
35.14
</pre></div>
</div>
</div>
<div class="section" id="sqlite-and-python-types">
<h2>11.13.5. SQLite and Python types<a class="headerlink" href="#sqlite-and-python-types" title="Permalink to this headline">¶</a></h2>
<div class="section" id="introduction">
<h3>11.13.5.1. Introduction<a class="headerlink" href="#introduction" title="Permalink to this headline">¶</a></h3>
SQLite natively supports the following types: <code class="docutils literal notranslate">NULL</code>, <code class="docutils literal notranslate">INTEGER</code>,
<code class="docutils literal notranslate">REAL</code>, <code class="docutils literal notranslate">TEXT</code>, <code class="docutils literal notranslate">BLOB</code>.
The following Python types can thus be sent to SQLite without any problem:
<table border="1" class="docutils">
<colgroup>
<col width="69%" />
<col width="31%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Python type</th>
<th class="head">SQLite type</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a></td>
<td><code class="docutils literal notranslate">NULL</code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a></td>
<td><code class="docutils literal notranslate">INTEGER</code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="functions.html#long" title="long"><code class="xref py py-class docutils literal notranslate">long</code></a></td>
<td><code class="docutils literal notranslate">INTEGER</code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a></td>
<td><code class="docutils literal notranslate">REAL</code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="functions.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> (UTF8-encoded)</td>
<td><code class="docutils literal notranslate">TEXT</code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="functions.html#unicode" title="unicode"><code class="xref py py-class docutils literal notranslate">unicode</code></a></td>
<td><code class="docutils literal notranslate">TEXT</code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="functions.html#buffer" title="buffer"><code class="xref py py-class docutils literal notranslate">buffer</code></a></td>
<td><code class="docutils literal notranslate">BLOB</code></td>
</tr>
</tbody>
</table>
This is how SQLite types are converted to Python types by default:
<table border="1" class="docutils">
<colgroup>
<col width="22%" />
<col width="78%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">SQLite type</th>
<th class="head">Python type</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><code class="docutils literal notranslate">NULL</code></td>
<td><a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate">None</code></a></td>
</tr>
<tr class="row-odd"><td><code class="docutils literal notranslate">INTEGER</code></td>
<td><a class="reference internal" href="functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a> or <a class="reference internal" href="functions.html#long" title="long"><code class="xref py py-class docutils literal notranslate">long</code></a>,
depending on size</td>
</tr>
<tr class="row-even"><td><code class="docutils literal notranslate">REAL</code></td>
<td><a class="reference internal" href="functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a></td>
</tr>
<tr class="row-odd"><td><code class="docutils literal notranslate">TEXT</code></td>
<td>depends on <a class="reference internal" href="#sqlite3.Connection.text_factory" title="sqlite3.Connection.text_factory"><code class="xref py py-attr docutils literal notranslate">text_factory</code></a>,
<a class="reference internal" href="functions.html#unicode" title="unicode"><code class="xref py py-class docutils literal notranslate">unicode</code></a> by default</td>
</tr>
<tr class="row-even"><td><code class="docutils literal notranslate">BLOB</code></td>
<td><a class="reference internal" href="functions.html#buffer" title="buffer"><code class="xref py py-class docutils literal notranslate">buffer</code></a></td>
</tr>
</tbody>
</table>
The type system of the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module is extensible in two ways: you can
store additional Python types in a SQLite database via object adaptation, and
you can let the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module convert SQLite types to different Python
types via converters.
</div>
<div class="section" id="using-adapters-to-store-additional-python-types-in-sqlite-databases">
<h3>11.13.5.2. Using adapters to store additional Python types in SQLite databases<a class="headerlink" href="#using-adapters-to-store-additional-python-types-in-sqlite-databases" title="Permalink to this headline">¶</a></h3>
As described before, SQLite supports only a limited set of types natively. To
use other Python types with SQLite, you must adapt them to one of the
sqlite3 module’s supported types for SQLite: one of NoneType, int, long, float,
str, unicode, buffer.
There are two ways to enable the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module to adapt a custom Python
type to one of the supported ones.
<div class="section" id="letting-your-object-adapt-itself">
<h4>11.13.5.2.1. Letting your object adapt itself<a class="headerlink" href="#letting-your-object-adapt-itself" title="Permalink to this headline">¶</a></h4>
This is a good approach if you write the class yourself. Let’s suppose you have
a class like this:
<div class="highlight-default notranslate"><div class="highlight"><pre>class Point(object):
 def __init__(self, x, y):
 self.x, self.y = x, y
</pre></div>
</div>
Now you want to store the point in a single SQLite column. First you’ll have to
choose one of the supported types first to be used for representing the point.
Let’s just use str and separate the coordinates using a semicolon. Then you need
to give your class a method <code class="docutils literal notranslate">__conform__(self, protocol)</code> which must return
the converted value. The parameter protocol will be <code class="xref py py-class docutils literal notranslate">PrepareProtocol</code>.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

class Point(object):
 def __init__(self, x, y):
 self.x, self.y = x, y

def __conform__(self, protocol):
 if protocol is sqlite3.PrepareProtocol:
 return &quot;%f;%f&quot; % (self.x, self.y)

p = Point(4.0, -3.2)
cur.execute(&quot;select ?&quot;, (p,))
print cur.fetchone()[0]
</pre></div>
</div>
</div>
<div class="section" id="registering-an-adapter-callable">
<h4>11.13.5.2.2. Registering an adapter callable<a class="headerlink" href="#registering-an-adapter-callable" title="Permalink to this headline">¶</a></h4>
The other possibility is to create a function that converts the type to the
string representation and register the function with <a class="reference internal" href="#sqlite3.register_adapter" title="sqlite3.register_adapter"><code class="xref py py-meth docutils literal notranslate">register_adapter()</code></a>.
<div class="admonition note">
Note
The type/class to adapt must be a <a class="reference internal" href="../glossary.html#term-new-style-class">new-style class</a>, i. e. it must have
<a class="reference internal" href="functions.html#object" title="object"><code class="xref py py-class docutils literal notranslate">object</code></a> as one of its bases.
</div>
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

def adapt_point(point):
 return &quot;%f;%f&quot; % (point.x, point.y)

sqlite3.register_adapter(Point, adapt_point)

p = Point(4.0, -3.2)
cur.execute(&quot;select ?&quot;, (p,))
print cur.fetchone()[0]
</pre></div>
</div>
The <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module has two default adapters for Python’s built-in
<a class="reference internal" href="datetime.html#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate">datetime.date</code></a> and <a class="reference internal" href="datetime.html#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate">datetime.datetime</code></a> types. Now let’s suppose
we want to store <a class="reference internal" href="datetime.html#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate">datetime.datetime</code></a> objects not in ISO representation,
but as a Unix timestamp.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
import datetime, time

def adapt_datetime(ts):
 return time.mktime(ts.timetuple())

sqlite3.register_adapter(datetime.datetime, adapt_datetime)

now = datetime.datetime.now()
cur.execute(&quot;select ?&quot;, (now,))
print cur.fetchone()[0]
</pre></div>
</div>
</div>
</div>
<div class="section" id="converting-sqlite-values-to-custom-python-types">
<h3>11.13.5.3. Converting SQLite values to custom Python types<a class="headerlink" href="#converting-sqlite-values-to-custom-python-types" title="Permalink to this headline">¶</a></h3>
Writing an adapter lets you send custom Python types to SQLite. But to make it
really useful we need to make the Python to SQLite to Python roundtrip work.
Enter converters.
Let’s go back to the <code class="xref py py-class docutils literal notranslate">Point</code> class. We stored the x and y coordinates
separated via semicolons as strings in SQLite.
First, we’ll define a converter function that accepts the string as a parameter
and constructs a <code class="xref py py-class docutils literal notranslate">Point</code> object from it.
<div class="admonition note">
Note
Converter functions always get called with a string, no matter under which
data type you sent the value to SQLite.
</div>
<div class="highlight-default notranslate"><div class="highlight"><pre>def convert_point(s):
 x, y = map(float, s.split(&quot;;&quot;))
 return Point(x, y)
</pre></div>
</div>
Now you need to make the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module know that what you select from
the database is actually a point. There are two ways of doing this:
<ul class="simple">
<li>Implicitly via the declared type</li>
<li>Explicitly via the column name</li>
</ul>
Both ways are described in section <a class="reference internal" href="#sqlite3-module-contents">Module functions and constants</a>, in the entries
for the constants <a class="reference internal" href="#sqlite3.PARSE_DECLTYPES" title="sqlite3.PARSE_DECLTYPES"><code class="xref py py-const docutils literal notranslate">PARSE_DECLTYPES</code></a> and <a class="reference internal" href="#sqlite3.PARSE_COLNAMES" title="sqlite3.PARSE_COLNAMES"><code class="xref py py-const docutils literal notranslate">PARSE_COLNAMES</code></a>.
The following example illustrates both approaches.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

def __repr__(self):
 return &quot;(%f;%f)&quot; % (self.x, self.y)

def convert_point(s):
 x, y = map(float, s.split(&quot;;&quot;))
 return Point(x, y)

# Register the adapter
sqlite3.register_adapter(Point, adapt_point)

# Register the converter
sqlite3.register_converter(&quot;point&quot;, convert_point)

#########################
# 1) Using declared types
con = sqlite3.connect(&quot;:memory:&quot;, detect_types=sqlite3.PARSE_DECLTYPES)
cur = con.cursor()
cur.execute(&quot;create table test(p point)&quot;)

#######################
# 1) Using column names
con = sqlite3.connect(&quot;:memory:&quot;, detect_types=sqlite3.PARSE_COLNAMES)
cur = con.cursor()
cur.execute(&quot;create table test(p)&quot;)

cur.execute(&quot;insert into test(p) values (?)&quot;, (p,))
cur.execute(&#39;select p as &quot;p [point]&quot; from test&#39;)
print &quot;with column names:&quot;, cur.fetchone()[0]
cur.close()
con.close()
</pre></div>
</div>
</div>
<div class="section" id="default-adapters-and-converters">
<h3>11.13.5.4. Default adapters and converters<a class="headerlink" href="#default-adapters-and-converters" title="Permalink to this headline">¶</a></h3>
There are default adapters for the date and datetime types in the datetime
module. They will be sent as ISO dates/ISO timestamps to SQLite.
The default converters are registered under the name “date” for
<a class="reference internal" href="datetime.html#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate">datetime.date</code></a> and under the name “timestamp” for
<a class="reference internal" href="datetime.html#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate">datetime.datetime</code></a>.
This way, you can use date/timestamps from Python without any additional
fiddling in most cases. The format of the adapters is also compatible with the
experimental SQLite date/time functions.
The following example demonstrates this.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3
import datetime

today = datetime.date.today()
now = datetime.datetime.now()

cur.execute(&quot;insert into test(d, ts) values (?, ?)&quot;, (today, now))
cur.execute(&quot;select d, ts from test&quot;)
row = cur.fetchone()
print today, &quot;=&gt;&quot;, row[0], type(row[0])
print now, &quot;=&gt;&quot;, row[1], type(row[1])

cur.execute(&#39;select current_date as &quot;d [date]&quot;, current_timestamp as &quot;ts [timestamp]&quot;&#39;)
row = cur.fetchone()
print &quot;current_date&quot;, row[0], type(row[0])
print &quot;current_timestamp&quot;, row[1], type(row[1])
</pre></div>
</div>
If a timestamp stored in SQLite has a fractional part longer than 6
numbers, its value will be truncated to microsecond precision by the
timestamp converter.
</div>
</div>
<div class="section" id="controlling-transactions">
<h2>11.13.6. Controlling Transactions<a class="headerlink" href="#controlling-transactions" title="Permalink to this headline">¶</a></h2>
By default, the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module opens transactions implicitly before a
Data Modification Language (DML) statement (i.e.
<code class="docutils literal notranslate">INSERT</code>/<code class="docutils literal notranslate">UPDATE</code>/<code class="docutils literal notranslate">DELETE</code>/<code class="docutils literal notranslate">REPLACE</code>), and commits transactions
implicitly before a non-DML, non-query statement (i. e.
anything other than <code class="docutils literal notranslate">SELECT</code> or the aforementioned).
So if you are within a transaction and issue a command like <code class="docutils literal notranslate">CREATE TABLE
...</code>, <code class="docutils literal notranslate">VACUUM</code>, <code class="docutils literal notranslate">PRAGMA</code>, the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module will commit implicitly
before executing that command. There are two reasons for doing that. The first
is that some of these commands don’t work within transactions. The other reason
is that sqlite3 needs to keep track of the transaction state (if a transaction
is active or not).
You can control which kind of <code class="docutils literal notranslate">BEGIN</code> statements sqlite3 implicitly executes
(or none at all) via the isolation_level parameter to the <a class="reference internal" href="#sqlite3.connect" title="sqlite3.connect"><code class="xref py py-func docutils literal notranslate">connect()</code></a>
call, or via the <code class="xref py py-attr docutils literal notranslate">isolation_level</code> property of connections.
If you want autocommit mode, then set <code class="xref py py-attr docutils literal notranslate">isolation_level</code> to <code class="docutils literal notranslate">None</code>.
Otherwise leave it at its default, which will result in a plain “BEGIN”
statement, or set it to one of SQLite’s supported isolation levels: “DEFERRED”,
“IMMEDIATE” or “EXCLUSIVE”.
</div>
<div class="section" id="using-sqlite3-efficiently">
<h2>11.13.7. Using <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> efficiently<a class="headerlink" href="#using-sqlite3-efficiently" title="Permalink to this headline">¶</a></h2>
<div class="section" id="using-shortcut-methods">
<h3>11.13.7.1. Using shortcut methods<a class="headerlink" href="#using-shortcut-methods" title="Permalink to this headline">¶</a></h3>
Using the nonstandard <code class="xref py py-meth docutils literal notranslate">execute()</code>, <code class="xref py py-meth docutils literal notranslate">executemany()</code> and
<code class="xref py py-meth docutils literal notranslate">executescript()</code> methods of the <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> object, your code can
be written more concisely because you don’t have to create the (often
superfluous) <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a> objects explicitly. Instead, the <a class="reference internal" href="#sqlite3.Cursor" title="sqlite3.Cursor"><code class="xref py py-class docutils literal notranslate">Cursor</code></a>
objects are created implicitly and these shortcut methods return the cursor
objects. This way, you can execute a <code class="docutils literal notranslate">SELECT</code> statement and iterate over it
directly using only a single call on the <a class="reference internal" href="multiprocessing.html#Connection" title="Connection"><code class="xref py py-class docutils literal notranslate">Connection</code></a> object.
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

persons = [
 (&quot;Hugo&quot;, &quot;Boss&quot;),
 (&quot;Calvin&quot;, &quot;Klein&quot;)
 ]

# Create the table
con.execute(&quot;create table person(firstname, lastname)&quot;)

# Fill the table
con.executemany(&quot;insert into person(firstname, lastname) values (?, ?)&quot;, persons)

# Print the table contents
for row in con.execute(&quot;select firstname, lastname from person&quot;):
 print row

print &quot;I just deleted&quot;, con.execute(&quot;delete from person&quot;).rowcount, &quot;rows&quot;
</pre></div>
</div>
</div>
<div class="section" id="accessing-columns-by-name-instead-of-by-index">
<h3>11.13.7.2. Accessing columns by name instead of by index<a class="headerlink" href="#accessing-columns-by-name-instead-of-by-index" title="Permalink to this headline">¶</a></h3>
One useful feature of the <a class="reference internal" href="#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate">sqlite3</code></a> module is the built-in
<a class="reference internal" href="#sqlite3.Row" title="sqlite3.Row"><code class="xref py py-class docutils literal notranslate">sqlite3.Row</code></a> class designed to be used as a row factory.
Rows wrapped with this class can be accessed both by index (like tuples) and
case-insensitively by name:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

cur = con.cursor()
cur.execute(&quot;select &#39;John&#39; as name, 42 as age&quot;)
for row in cur:
 assert row[0] == row[&quot;name&quot;]
 assert row[&quot;name&quot;] == row[&quot;nAmE&quot;]
 assert row[1] == row[&quot;age&quot;]
 assert row[1] == row[&quot;AgE&quot;]
</pre></div>
</div>
</div>
<div class="section" id="using-the-connection-as-a-context-manager">
<h3>11.13.7.3. Using the connection as a context manager<a class="headerlink" href="#using-the-connection-as-a-context-manager" title="Permalink to this headline">¶</a></h3>
<div class="versionadded">
New in version 2.6.
</div>
Connection objects can be used as context managers
that automatically commit or rollback transactions. In the event of an
exception, the transaction is rolled back; otherwise, the transaction is
committed:
<div class="highlight-default notranslate"><div class="highlight"><pre>import sqlite3

# Successful, con.commit() is called automatically afterwards
with con:
 con.execute(&quot;insert into person(firstname) values (?)&quot;, (&quot;Joe&quot;,))

# con.rollback() is called after the with block finishes with an exception, the
# exception is still raised and must be caught
try:
 with con:
 con.execute(&quot;insert into person(firstname) values (?)&quot;, (&quot;Joe&quot;,))
except sqlite3.IntegrityError:
 print &quot;couldn&#39;t add Joe twice&quot;
</pre></div>
</div>
</div>
</div>
<div class="section" id="common-issues">
<h2>11.13.8. Common issues<a class="headerlink" href="#common-issues" title="Permalink to this headline">¶</a></h2>
<div class="section" id="multithreading">
<h3>11.13.8.1. Multithreading<a class="headerlink" href="#multithreading" title="Permalink to this headline">¶</a></h3>
Older SQLite versions had issues with sharing connections between threads.
That’s why the Python module disallows sharing connections and cursors between
threads. If you still try to do so, you will get an exception at runtime.
The only exception is calling the <a class="reference internal" href="#sqlite3.Connection.interrupt" title="sqlite3.Connection.interrupt"><code class="xref py py-meth docutils literal notranslate">interrupt()</code></a> method, which
only makes sense to call from a different thread.
Footnotes
<table class="docutils footnote" frame="void" id="f1" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label">[1]</td><td>(<a class="fn-backref" href="#id1">1</a>, <a class="fn-backref" href="#id2">2</a>) The sqlite3 module is not built with loadable extension support by
default, because some platforms (notably Mac OS X) have SQLite libraries
which are compiled without this feature. To get loadable extension support,
you must modify setup.py and remove the line that sets
SQLITE_OMIT_LOAD_EXTENSION.</td></tr>
</tbody>
</table>
</div>
</div>
</div>

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 <h3><a href="../contents.html">Table Of Contents</a></h3>
 <ul>
<li><a class="reference internal" href="#">11.13. <code class="docutils literal notranslate">sqlite3</code> — DB-API 2.0 interface for SQLite databases</a><ul>
<li><a class="reference internal" href="#module-functions-and-constants">11.13.1. Module functions and constants</a></li>
<li><a class="reference internal" href="#connection-objects">11.13.2. Connection Objects</a></li>
<li><a class="reference internal" href="#cursor-objects">11.13.3. Cursor Objects</a></li>
<li><a class="reference internal" href="#row-objects">11.13.4. Row Objects</a></li>
<li><a class="reference internal" href="#sqlite-and-python-types">11.13.5. SQLite and Python types</a><ul>
<li><a class="reference internal" href="#introduction">11.13.5.1. Introduction</a></li>
<li><a class="reference internal" href="#using-adapters-to-store-additional-python-types-in-sqlite-databases">11.13.5.2. Using adapters to store additional Python types in SQLite databases</a><ul>
<li><a class="reference internal" href="#letting-your-object-adapt-itself">11.13.5.2.1. Letting your object adapt itself</a></li>
<li><a class="reference internal" href="#registering-an-adapter-callable">11.13.5.2.2. Registering an adapter callable</a></li>
</ul>
</li>
<li><a class="reference internal" href="#converting-sqlite-values-to-custom-python-types">11.13.5.3. Converting SQLite values to custom Python types</a></li>
<li><a class="reference internal" href="#default-adapters-and-converters">11.13.5.4. Default adapters and converters</a></li>
</ul>
</li>
<li><a class="reference internal" href="#controlling-transactions">11.13.6. Controlling Transactions</a></li>
<li><a class="reference internal" href="#using-sqlite3-efficiently">11.13.7. Using <code class="docutils literal notranslate">sqlite3</code> efficiently</a><ul>
<li><a class="reference internal" href="#using-shortcut-methods">11.13.7.1. Using shortcut methods</a></li>
<li><a class="reference internal" href="#accessing-columns-by-name-instead-of-by-index">11.13.7.2. Accessing columns by name instead of by index</a></li>
<li><a class="reference internal" href="#using-the-connection-as-a-context-manager">11.13.7.3. Using the connection as a context manager</a></li>
</ul>
</li>
<li><a class="reference internal" href="#common-issues">11.13.8. Common issues</a><ul>
<li><a class="reference internal" href="#multithreading">11.13.8.1. Multithreading</a></li>
</ul>
</li>
</ul>
</li>
</ul>

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