How Can I Efficiently Retrieve a Single SQL Result in Python?

Python elegantly gets a single SQL result

When executing SQL SELECT queries using Python and SQLite, nested loops are often required to extract a single value. Consider the following example:

<code class="language-python">conn = sqlite3.connect('db_path.db')
cursor = conn.cursor()
cursor.execute("SELECT MAX(value) FROM table")

for row in cursor:
    for elem in row:
        maxVal = elem</code>

This method requires iterating over the result rows and columns to get the desired value. However, individual results can be retrieved more efficiently using Cursor.fetchone().

The

fetchone() method takes the first row of the result set and returns it as a tuple. To access the value directly, use the following syntax:

<code class="language-python">maxVal = cursor.fetchone()[0]</code>

In this line, we use fetchone() to get the first row from the query result and then extract the first element of the tuple, which contains the maximum value. This simplifies the code and improves its readability.

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