TRUNCATE TABLE
Description
The TRUNCATE TABLE statement removes all the rows from a table or partition(s). The table must not be a view 
or an external/temporary table. In order to truncate multiple partitions at once, the user can specify the partitions 
in partition_spec. If no partition_spec is specified it will remove all partitions in the table.
Syntax
TRUNCATE TABLE table_identifier [ partition_spec ]Parameters
- table_identifier
- 
    Specifies a table name, which may be optionally qualified with a database name.
 Syntax:[ database_name. ] table_name
- partition_spec
- 
    An optional parameter that specifies a comma separated list of key and value pairs
    for partitions.
 Syntax:PARTITION ( partition_col_name = partition_col_val [ , ... ] )
Examples
--Create table Student with partition
CREATE TABLE Student ( name String, rollno INT) PARTITIONED BY (age int);
SELECT * from Student;
+-------+---------+------+--+
| name  | rollno  | age  |
+-------+---------+------+--+
| ABC   | 1       | 10   |
| DEF   | 2       | 10   |
| XYZ   | 3       | 12   |
+-------+---------+------+--+
-- Removes all rows from the table in the partition specified
TRUNCATE TABLE Student partition(age=10);
--After truncate execution, records belonging to partition age=10 are removed
SELECT * from Student;
+-------+---------+------+--+
| name  | rollno  | age  |
+-------+---------+------+--+
| XYZ   | 3       | 12   |
+-------+---------+------+--+
-- Removes all rows from the table from all partitions
TRUNCATE TABLE Student;
SELECT * from Student;
+-------+---------+------+--+
| name  | rollno  | age  |
+-------+---------+------+--+
+-------+---------+------+--+
No rows selected 