Package org.apache.derby.iapi.db
Class OptimizerTrace
- java.lang.Object
-
- org.apache.derby.iapi.db.OptimizerTrace
-
public class OptimizerTrace extends java.lang.Object
This class provides static methods for controlling the optimizer tracing in a Derby database.
-
-
Constructor Summary
Constructors Constructor Description OptimizerTrace()
-
Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static java.lang.String
getOptimizerTraceOutput()
Get the optimizer trace output for the last optimized query as a String.static OptTrace
getOptimizerTracer()
Get the current optimizer tracer, if any.static void
setOptimizerTrace(boolean onOrOff)
Turn default optimizer tracing on or off.static void
setOptimizerTracer(OptTrace tracer)
Install an optimizer tracer (to enable tracing) or uninstall the current optimizer tracer (to disable tracing).
-
-
-
Method Detail
-
setOptimizerTrace
public static void setOptimizerTrace(boolean onOrOff)
Turn default optimizer tracing on or off.- Parameters:
onOrOff
- Whether to turn optimizer tracing on (true) or off (false).
-
setOptimizerTracer
public static void setOptimizerTracer(OptTrace tracer)
Install an optimizer tracer (to enable tracing) or uninstall the current optimizer tracer (to disable tracing).- Parameters:
tracer
- Null if tracing is being turned off, otherwise an optimizer tracer
-
getOptimizerTracer
public static OptTrace getOptimizerTracer()
Get the current optimizer tracer, if any.
-
getOptimizerTraceOutput
public static java.lang.String getOptimizerTraceOutput()
Get the optimizer trace output for the last optimized query as a String.- Returns:
- The optimizer trace output for the last optimized query as a String. Null will be returned if optimizer trace output is off or not supported or no trace output was found or an exception occurred.
-
-