(!) sqldf works with H2, MySQL and PostgreSQL too - its not limited to SQLite. (2) Most alternatives to SQL available in R don't work well with complex multi-w

(!) sqldf works with H2, MySQL and PostgreSQL too - its not limited to SQLite. (2) Most alternatives to SQL available in R don't work well with complex multi-way joins. You wind up materializing the full outer join first which can be quite problematic. (3) sqldf is fast enough and R is slow enough that quite often sqldf is faster than base R so if R is fast enough for you then its likely that sqldf is too. (4) The speed is often the last thing you need to worry about. The ability to express a query in a familiar way (if you know SQL) is often the more important consideration than having to learn a new system.