I do not know what is faster, never tested it for speed differences, but there is no need to create a temporary variable to hold the SQL command and then execute it, so I guess it should be faster? I also think is cleaner this way, but that is a way too personal opinion.
*EDIT, well I see your other message now
"The five senses obstruct or deform the apprehension of reality."
Jorge L. Borges?
"Premature optimization is the root of all evil in programming."
Donald Knuth, repeating C. A. R. Hoare
"To die for a religion is easier than to live it absolutely"
Jorge L. Borges