PHP trace context in queries

Adding trace context to application queries provides the ability to correlate the queries from a traced transaction, and if sampled, the queries to the transaction trace detail. This feature is also a requirement for the integration of APM with DBO.

Enabling

Trace context propagation to queries is disabled by default. It can be enabled in the PHP Library using this configuration option:

Trace context is inserted only for statements from a transaction sampled for detailed tracing.

Trace context is not inserted into server-side prepared statements and stored procedures.

Database type	Client library/framework	Notes
MySQL	PDO MySQLi	Queries with short-lived connections might not be sampled due to MySql Performance Schema behavior.
PostgreSQL	PDO	Short-lived queries, or queries with short-lived connections might not be sampled based on the DBO Agent's polling interval.