Looks like there is currently a big misunderstanding here.
If i’m understanding @Maselia correctly the question is how to use GVM to scan e.g. a web application for SQL injections, not how to use SQL queries on the gvmd database to run a specific scan.
If this is correctly please have a look at:
Also please note that GVM is no full web application scanner (WAS) so you might need to use a separate, dedicated WAS software to find SQL injections in your application.