How to Stream Large Result Sets Efficiently with MySQLDB\'s SScursor?

Efficient Usage of MySQLDB's SScursor for Large Result Sets

When working with massive result sets in MySQL databases, memory consumption can become a concern. The MySQLDB library offers the SScursor class to mitigate this issue, providing a more efficient way to handle large data volumes.

Memory Usage of fetchall()

Contrary to popular belief, executing fetchall() on both base cursors and SScursors consumes the same amount of memory. It allocates buffers large enough to hold the entire result set in memory.

Streaming with SScursor

The strength of SScursors lies in their ability to iterate over results without loading the entire dataset into memory. To achieve streaming with an SScursor:

1. Use a generator: You can create a generator that yields each row one by one. For example:

<code class="python">def stream_rows(cursor):
    for row in cursor:
        yield row</code>

2. Iterate with a for loop: Iterate over the SScursor directly using a for loop:

<code class="python">for row in cursor:
    # Process row</code>

3. Use a fetchone() loop: While not as memory-efficient as the above methods, you can fetch rows one at a time with fetchone().

Most Efficient Streaming Method

The most efficient streaming method is to use a generator as it avoids the overhead of an extra loop. The generator can be passed to other functions or used directly for processing and filtering operations.

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