How to View the Actual Query Executed by MySQLdb?

How to View the Actual Query Executed by MySQLdb

When debugging database queries in Python using MySQLdb, it can be helpful to examine the exact query being executed, especially after parameterization. This can aid in identifying any errors or discrepancies between the intended query and its actual execution.

Accessing the Executed Query

In MySQLdb version 1.2.2, the Cursor object does not provide an explicit Cursor.info() method for retrieving query information. However, there is an attribute called cursor._last_executed that holds the last executed query string. This attribute is accessible even when an exception occurs during query execution.

Usage Example

To utilize this attribute for debugging purposes, you can access it after executing a query as follows:

<code class="python">import MySQLdb

db = MySQLdb.connect(... )
cursor = db.cursor()

# Execute a query with parameters
query = "SELECT * FROM users WHERE name = %s"
cursor.execute(query, ("John", ))

# Print the actual query executed
print(cursor._last_executed)</code>

Benefits

Using cursor._last_executed offers several benefits over other debugging techniques such as profiling or MySQL query logging:

• It is easier to implement and use in production environments.
• It does not have a significant performance impact.
• It provides immediate access to the executed query without the need for additional correlation or log parsing.

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