Advanced Oracle PL/SQL Programming with Packages

5.28. PLVtrc: Trace Facility

The PLVtrc (PL/Vision TRaCe) package provides a generic trace facility for PL/SQL applications for use in debugging. See Chapter 21 for details.

5.28.1. Package constants

c_top_pos CONSTANT INTEGER := 0;

Name of position of top module in the call stack. The argument you would pass to the PLVtrc.module function to retrieve the topmost program in the execution call stack.

c_last_pos CONSTANT INTEGER := 2;

Name of position of most recent module in call stack. The argument you would pass to the PLVtrc.module function to retrieve the last program executed before the call to PLVtrc.module.

5.28.2. Controlling trace activity

PROCEDURE turn_on;

Turns on the trace, enabling output from calls to the programs described below.

PROCEDURE turn_off;

Turns off the trace.

FUNCTION tracing RETURN BOOLEAN;

Returns TRUE if the trace is active.

5.28.3. Writing to the PL/Vision log

PROCEDURE log;

Turns on logging of trace message to the PL/Vision log (see the PLVlog package), in addition to displaying the trace.

PROCEDURE nolog;

Turns off logging (the default).

FUNCTION logging RETURN BOOLEAN;

Returns TRUE if logging of trace messages is currently turned on.

5.28.4. Displaying current module

PROCEDURE dispmod;

Turns on display of current module when showing the trace message.

PROCEDURE nodispmod;

Turns off display of current module (the default).

FUNCTION displaying_module RETURN BOOLEAN;

Returns TRUE if PLVtrc is displaying the current module.