Debugger Modes

The Oracle PL/SQL Debugger operates in these three modes:

Direct Database Debugging

The Direct Database Debugging mode allows you to debug PL/SQL code directly from Server Explorer. When you use the Direct Database Debugging mode, you do not need a Visual Studio solution or .NET code. By right-clicking on a procedure or function in Server Explorer, you can step into a PL/SQL procedure or function. Any arguments required by the procedure must be entered by hand. This limits the use of this feature to procedures or functions that have scalar parameter values.
Multitier Application Debugging

This mode allows you to seamlessly debug both .NET and PL/SQL code from within a single Visual Studio instance. You can step directly from your .NET code into the PL/SQL code and back out again passing live data and debugging that data.
External Application Debugging

External Application Debugging allows you to dedicate an instance of Visual Studio solely for waiting on a breakpoint to be called in a PL/SQL stored procedure or function, and then debug it with that instance of Visual Studio. This is particularly useful when the stored procedure or function is called by a middle tier web server. However any Oracle client running on any operating system may call the stored procedure or function.