Quiz

1:	The BENCHMARK() function returns the result of the benchmarked expression the time taken to execute the benchmarked expression zero, regardless of the parameters none of the above
2:	You run EXPLAIN on a query and it tells you that the type for one of the tables in the join is ALL . This means that only one row will be read from the table all the rows with matching index values will be read from the table all of the index will be scanned all of the table will be scanned
3:	You run EXPLAIN on a query and it tells you that the type for one of the tables in the join is eq_ref . This means that only one row will be read from the table all the rows with matching index values will be read from the table all of the index will be scanned all of the table will be scanned
4:	You run EXPLAIN on a query and it tells you that the type for one of the tables in the join is index . This means that only one row will be read from the table all the rows with matching index values will be read from the table all of the index will be scanned all of the table will be scanned
5:	The output of EXPLAIN tells you that MySQL is joining two tables in a suboptimal order. You should run ANALYZE TABLE on the two tables force the join order using STRAIGHT JOIN either a) or b) neither a) nor b)