2011/6/3 Stéphane MANKOWSKI <steph...@mankowski.fr> > > 4-EXPLAIN QUERY PLAN SELECT total, total+1, total+2 FROM v_c > returns: > SCAN TABLE c (~74 rows) > EXECUTE CORRELATED SCALAR SUBQUERY 1 > SEARCH TABLE a USING INDEX a_r_a_id (r_a_id=?) (~88 rows) > EXECUTE CORRELATED SCALAR SUBQUERY 2 > SEARCH TABLE a USING INDEX a_r_a_id (r_a_id=?) (~88 rows) > EXECUTE CORRELATED SCALAR SUBQUERY 3 > SEARCH TABLE a USING INDEX a_r_a_id (r_a_id=?) (~88 rows) > > For me this is not optimized (but I am not a db specialist) because the > computation of "total" is done 3 times instead of only one. >
SQLite does not currently implement common subexpression elimination. -- D. Richard Hipp d...@sqlite.org _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
