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Jure Šorn 2 years ago
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  1. 9
      README.md
  2. 25
      index.html

9
README.md
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@ -1868,16 +1868,13 @@ SQLite
------
**A server-less database engine that stores each database into a separate file.**
### Connect
**Opens a connection to the database file. Creates a new file if path doesn't exist.**
```python
import sqlite3
<conn> = sqlite3.connect(<path>) # Also ':memory:'.
<conn> = sqlite3.connect(<path>) # Opens existing or new file. Also ':memory:'.
<conn>.close() # Closes the connection.
```
### Read
**Returned values can be of type str, int, float, bytes or None.**
```python
<cursor> = <conn>.execute('<query>') # Can raise a subclass of sqlite3.Error.
<tuple> = <cursor>.fetchone() # Returns next row. Also next(<cursor>).
@ -1898,13 +1895,13 @@ with <conn>: # Exits the block with commit()
```
### Placeholders
* **Passed values can be of type str, int, float, bytes, None, bool, datetime.date or datetime.datetime.**
* **Bools will be stored and returned as ints and dates as [ISO formatted strings](#encode).**
```python
<conn>.execute('<query>', <list/tuple>) # Replaces '?'s in query with values.
<conn>.execute('<query>', <dict/namedtuple>) # Replaces ':<key>'s with values.
<conn>.executemany('<query>', <coll_of_above>) # Runs execute() multiple times.
```
* **Passed values can be of type str, int, float, bytes, None, bool, datetime.date or datetime.datetime.**
* **Bools will be stored and returned as ints and dates as [ISO formatted strings](#encode).**
### Example
**Values are not actually saved in this example because `'conn.commit()'` is omitted!**

25
index.html
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@ -54,7 +54,7 @@
<body>
<header>
<aside>September 16, 2022</aside>
<aside>September 19, 2022</aside>
<a href="https://gto76.github.io" rel="author">Jure Šorn</a>
</header>
@ -1557,20 +1557,17 @@ CompletedProcess(args=[<span class="hljs-string">'bc'</span>, <span class="hljs-
writer.writerows(rows)
</code></pre></div>
<div><h2 id="sqlite"><a href="#sqlite" name="sqlite">#</a>SQLite</h2><p><strong>A server-less database engine that stores each database into a separate file.</strong></p><div><h3 id="connect">Connect</h3><p><strong>Opens a connection to the database file. Creates a new file if path doesn't exist.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">import</span> sqlite3
&lt;conn&gt; = sqlite3.connect(&lt;path&gt;) <span class="hljs-comment"># Also ':memory:'.</span>
<div><h2 id="sqlite"><a href="#sqlite" name="sqlite">#</a>SQLite</h2><p><strong>A server-less database engine that stores each database into a separate file.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">import</span> sqlite3
&lt;conn&gt; = sqlite3.connect(&lt;path&gt;) <span class="hljs-comment"># Opens existing or new file. Also ':memory:'.</span>
&lt;conn&gt;.close() <span class="hljs-comment"># Closes the connection.</span>
</code></pre></div></div>
</code></pre></div>
<div><h3 id="read-1">Read</h3><p><strong>Returned values can be of type str, int, float, bytes or None.</strong></p><pre><code class="python language-python hljs">&lt;cursor&gt; = &lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>) <span class="hljs-comment"># Can raise a subclass of sqlite3.Error.</span>
<div><h3 id="read-1">Read</h3><pre><code class="python language-python hljs">&lt;cursor&gt; = &lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>) <span class="hljs-comment"># Can raise a subclass of sqlite3.Error.</span>
&lt;tuple&gt; = &lt;cursor&gt;.fetchone() <span class="hljs-comment"># Returns next row. Also next(&lt;cursor&gt;).</span>
&lt;list&gt; = &lt;cursor&gt;.fetchall() <span class="hljs-comment"># Returns remaining rows. Also list(&lt;cursor&gt;).</span>
</code></pre></div>
<div><h3 id="write-1">Write</h3><pre><code class="python language-python hljs">&lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>) <span class="hljs-comment"># Can raise a subclass of sqlite3.Error.</span>
&lt;conn&gt;.commit() <span class="hljs-comment"># Saves all changes since the last commit.</span>
&lt;conn&gt;.rollback() <span class="hljs-comment"># Discards all changes since the last commit.</span>
@ -1580,15 +1577,15 @@ CompletedProcess(args=[<span class="hljs-string">'bc'</span>, <span class="hljs-
&lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>) <span class="hljs-comment"># depending on whether any exception occurred.</span>
</code></pre></div>
<div><h3 id="placeholders">Placeholders</h3><ul>
<li><strong>Passed values can be of type str, int, float, bytes, None, bool, datetime.date or datetime.datetime.</strong></li>
<li><strong>Bools will be stored and returned as ints and dates as <a href="#encode">ISO formatted strings</a>.</strong></li>
</ul><pre><code class="python language-python hljs">&lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>, &lt;list/tuple&gt;) <span class="hljs-comment"># Replaces '?'s in query with values.</span>
<div><h3 id="placeholders">Placeholders</h3><pre><code class="python language-python hljs">&lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>, &lt;list/tuple&gt;) <span class="hljs-comment"># Replaces '?'s in query with values.</span>
&lt;conn&gt;.execute(<span class="hljs-string">'&lt;query&gt;'</span>, &lt;dict/namedtuple&gt;) <span class="hljs-comment"># Replaces ':&lt;key&gt;'s with values.</span>
&lt;conn&gt;.executemany(<span class="hljs-string">'&lt;query&gt;'</span>, &lt;coll_of_above&gt;) <span class="hljs-comment"># Runs execute() multiple times.</span>
</code></pre></div>
<ul>
<li><strong>Passed values can be of type str, int, float, bytes, None, bool, datetime.date or datetime.datetime.</strong></li>
<li><strong>Bools will be stored and returned as ints and dates as <a href="#encode">ISO formatted strings</a>.</strong></li>
</ul>
<div><h3 id="example">Example</h3><p><strong>Values are not actually saved in this example because <code class="python hljs"><span class="hljs-string">'conn.commit()'</span></code> is omitted!</strong></p><pre><code class="python language-python hljs"><span class="hljs-meta">&gt;&gt;&gt; </span>conn = sqlite3.connect(<span class="hljs-string">'test.db'</span>)
<span class="hljs-meta">&gt;&gt;&gt; </span>conn.execute(<span class="hljs-string">'CREATE TABLE person (person_id INTEGER PRIMARY KEY, name, height)'</span>)
<span class="hljs-meta">&gt;&gt;&gt; </span>conn.execute(<span class="hljs-string">'INSERT INTO person VALUES (NULL, ?, ?)'</span>, (<span class="hljs-string">'Jean-Luc'</span>, <span class="hljs-number">187</span>)).lastrowid
@ -2906,7 +2903,7 @@ $ pyinstaller script.py --add-data '&lt;path&gt;:.' <span class="hljs-comment">
<footer>
<aside>September 16, 2022</aside>
<aside>September 19, 2022</aside>
<a href="https://gto76.github.io" rel="author">Jure Šorn</a>
</footer>

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