10.15 Tracing the Optimizer

10.15.1 Typical Usage

10.15.2 System Variables Controlling Tracing

10.15.3 Traceable Statements

10.15.4 Tuning Trace Purging

10.15.5 Tracing Memory Usage

10.15.6 Privilege Checking

10.15.7 Interaction with the --debug Option

10.15.8 The optimizer_trace System Variable

10.15.9 The end_markers_in_json System Variable

10.15.10 Selecting Optimizer Features to Trace

10.15.11 Trace General Structure

10.15.12 Example

10.15.13 Displaying Traces in Other Applications

10.15.14 Preventing the Use of Optimizer Trace

10.15.15 Testing Optimizer Trace

10.15.16 Optimizer Trace Implementation

The MySQL optimizer includes the capability to perform tracing; the interface is provided by a set of optimizer_trace_xxx system variables and the INFORMATION_SCHEMA.OPTIMIZER_TRACE table.