|Unnamed Parameter Markers|
The question marker symbol is probably the most supported parameter marker among the supported databases. It is also the most unintuitive marker since the user has to remember the order of question marks and the corresponding values.
Since there is no name associated with it, DbVisualizer shows these as Parameter 1, Parameter 2 and so on in the prompt window.
There is no technical difference between how unnamed and named parameter markers are handled internally in DbVisualizer or when processed by the database. All are bound with a prepared SQL statement.
Use named in favor of unnamed parameter markers if there is support in the target database based on the easier reading of named markers. Read more about unnamed parameter markers.