I don't know how anyone could use a database in a speed game. I think what gives people an advantage in a speed game would be using an engine, which can think through the position extremely quickly and suggest good moves that can be played fairly quickly in the time constraints of the game. Using the database gives you the top move played in a position as well as various other moves along with the percentage results after playing that (an only that) move. To use it properly, you'll have to look into the various moves and how they played out in order to judge them properly. This would eat up a rapid or blitz player's entire time and they'll lose before move 10.
Even in 3-day per move games, I find that by about move 10-15 (sometimes earlier) people stray from the existing lines in the database and you're on your own anyhow.
Some people play TCs above 30|0, though.
I don't know how anyone could use a database in a speed game. I think what gives people an advantage in a speed game would be using an engine, which can think through the position extremely quickly and suggest good moves that can be played fairly quickly in the time constraints of the game. Using the database gives you the top move played in a position as well as various other moves along with the percentage results after playing that (an only that) move. To use it properly, you'll have to look into the various moves and how they played out in order to judge them properly. This would eat up a rapid or blitz player's entire time and they'll lose before move 10.
Even in 3-day per move games, I find that by about move 10-15 (sometimes earlier) people stray from the existing lines in the database and you're on your own anyhow.