You can set breakpoints at executable source lines in PL/SQL program units, libraries and packages, and triggers.
To create a breakpoint:
Tip: You can also double-click in the left margin next to a source line to set a breakpoint there or choose Debug | Insert/Remove Breakpoint from the main menu.
When your application runs in debug mode, execution is suspended upon reaching a line of code that has an enabled breakpoint. Upon suspension, the PL/SQL Editor opens and displays the source unit with a pointer at the line of code where the suspension point is hit.
When using the debugger across different machines to debug FMX and FMB files, the target files that are to be debugged must be regenerated on the target machine if you move them.
For example, if you have an FMB and an FMX that are generated on machine A, and you copy them over to machine B, and if your client debugger is on machine C, any breakpoints that you set on the files on machine B will be ignored by the debugger. You will need to regenerate the files on machine B in order for the client debugger on machine C to see the breakpoints.
About Breakpoints and Executable Source Lines