The exple in https://www.w3schools.com/CSSref/playit.asp?filename=playcss_quotes&preval=%27\2039%27%20%27\203A%27%20%27\00AB%27%20%27\00BB%27
(and possibly in other places) uses examples with the upper quote sign first an the lower quote sign at the end.
The correct order in German, Austrian and possibly other countries e.g. Switzerland is:
„quoted phrase“
which query should be used when you have this
INSERT INTO `$variable` (col1, col2) VALUES .....
The question is regarding $variable. is it " ", ' ' ,` ` .
?