There are implicit type casting rules that allow Drill to cast
automatically between certain types. It is not special in this respect,
you will find you can write the same sort of WHERE clause in many SQL
engines.
On 2022/04/05 09:26, Wes Peng wrote:
thanks James.
For the queries below, I got the birth_date as varchar type, but why
this column can be compared as date type?
apache drill (dfs.pyh)> select typeOf(birth_date) from foodmart limit 1 ;
+---------+
| EXPR$0 |
+---------+
| VARCHAR |
+---------+
1 row selected (0.234 seconds)
apache drill (dfs.pyh)> select * from foodmart where birth_date >
'1970-01-01';
+-------------+--------------------+-------------------------+------------+---------+---------------------+
| employee_id | full_name | position_title |
birth_date | salary | education_level |
+-------------+--------------------+-------------------------+------------+---------+---------------------+
| 9 | Brenda Blumberg | Store Manager |
1979-06-23 | 17000.0 | Graduate Degree |
| 12 | Jewel Creek | Store Manager |
1971-10-18 | 8500.0 | Graduate Degree |
| 13 | Peggy Medina | Store Manager |
1975-10-12 | 15000.0 | Bachelors Degree |
Regards
On 2022/4/5 2:37 下午, James Turton wrote:
select typeOf(employee_id) from foodmart limit 1
