How Can I See the Actual SQL Query Executed by My PDO Prepared Statement?

How to Obtain the Raw SQL Query Executed by PDO Prepared Statements

When debugging PDO prepared statements, it is often helpful to have access to the raw SQL query string that was executed. However, it is not immediately clear how to do this, as prepared statements typically involve the separation of parameter data from the actual query.

PDO's Internal Handling of Prepared Statements

Unlike regular SQL statements, where the query and parameters are sent to the database together, prepared statements are split into two parts:

• The SQL statement is sent to the database separately during the prepare() method invocation.
• The parameter values are sent during the execute() method invocation.

This separation prevents SQL injection attacks. However, it also means that PDO doesn't have direct access to the combined query string with interpolated parameter values.

The PDO::ATTR_EMULATE_PREPARES Option

To access the interpolated query string, one option is to set the PDO::ATTR_EMULATE_PREPARES attribute. This mode forces PDO to emulate prepared queries on the client side, combining the query and parameters before sending them to the database.

However, this method caveats:

• You will lose the security benefits of true prepared statements.
• PDO still doesn't expose the interpolated query string explicitly.

Using the MySQL General Query Log

If you're using MySQL, you can enable the general query log to capture the interpolated query string. However, this approach requires that the query has already been executed.

Other Methods

Unfortunately, there is no reliable way to get the interpolated query string directly from PDO without resorting to emulation or logging.

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