| set hive.explain.user=true; |
| |
| create table d1(d date); |
| -- tblproperties('transactional'='false'); |
| |
| insert into d1 values |
| ('2010-10-01'), |
| ('2010-10-02'), |
| ('2010-10-03'), |
| ('2010-10-04'), |
| ('2010-10-05'), |
| ('2010-10-06'), |
| ('2010-10-07'), |
| ('2010-10-08'), |
| ('2010-10-09'), |
| ('2010-10-10'); |
| |
| analyze table d1 compute statistics for columns; |
| |
| desc formatted d1; |
| desc formatted d1 d; |
| |
| explain |
| select 'stats: FIL ~0 read',count(1) from d1 where d < '2010-03-01'; |
| |
| explain |
| select 'stats: FIL estimate some read',count(1) from d1 where d < '2010-10-03'; |
| |
| explain |
| select 'stats: FIL estimate all read',count(1) from d1 where d < '2010-11-03'; |