How Can I Retrieve the Final, Parameter-Interpolated SQL Query from a PDO Prepared Statement?

Retrieving the Raw SQL Query from PDO Prepared Statements

In the context of prepared statements, the concept of a "raw SQL query string" is not straightforward. When PDOStatement::execute() is invoked on a prepared statement, the SQL statement that gets executed is distinct from the prepared statement itself.

Accessing the final SQL query, interpolated with parameter values, is not a straightforward process inherent to prepared statements. Parameters are not consolidated with the prepared statement on the client-side, making it inaccessible to PDO.

The SQL statement is sent to the database server during the prepare() operation, while parameters are transmitted separately when execute() is called. MySQL maintains a general query log that reveals the final SQL with embedded values following execute(). However, this log is external to PDO and does not represent the "raw" query string.

One workaround involves setting the PDO attribute PDO::ATTR_EMULATE_PREPARES. In this mode, PDO interpolates parameters into the SQL query prior to executing it. However, this method compromises the efficacy of prepared statements.

The PDOStatement object's $queryString property may seem like a potential solution, but it is only set during object initialization and doesn't reflect parameter interpolation. Exposing the rewritten query as a feature would be beneficial, but it would still not fulfill the requirement unless PDO::ATTR_EMULATE_PREPARES is used.

Utilizing a MySQL server's general query log provides a workaround as it records the rewritten query. Nonetheless, this is only applicable during logging, not query execution.

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