Description
cast(expr as dateType) cast the expr to dataType. return the value of dataType. The following conversion rules are used:
+------------+--------+--------+---------+-------------+--------+--------+
| Src/Target | STRING | NUMBER | BOOLEAN | TIMESTAMP | DATE | TIME |
+------------+--------+--------+---------+-------------+--------+--------+
| STRING | | Note1 | Note1 | TIMESTAMP() | DATE() | TIME() |
+------------+--------+--------+---------+-------------+--------+--------+
| NUMBER | Note1 | | v!=0 | N/A | N/A | N/A |
+------------+--------+--------+---------+-------------+--------+--------+
| BOOLEAN | Note1 | v?1:0 | | N/A | N/A | N/A |
+------------+--------+--------+---------+-------------+--------+--------+
| TIMESTAMP | Note1 | N/A | N/A | | DATE() | TIME() |
+------------+--------+--------+---------+-------------+--------+--------+
| DATE | Note1 | N/A | N/A | N/A | | N/A |
+------------+--------+--------+---------+-------------+--------+--------+
| TIME | Note1 | N/A | N/A | N/A | N/A | |
+------------+--------+--------+---------+-------------+--------+--------+
Cast to string example:
os> source=people | eval `cbool` = CAST(true as string), `cint` = CAST(1 as string), `cdate` = CAST(CAST('2012-08-07' as date) as string) | fields `cbool`, `cint`, `cdate`
fetched rows / total rows = 1/1
+---------+--------+------------+
| cbool | cint | cdate |
|---------+--------+------------|
| true | 1 | 2012-08-07 |
+---------+--------+------------+
Cast to number example:
os> source=people | eval `cbool` = CAST(true as int), `cstring` = CAST('1' as int) | fields `cbool`, `cstring`
fetched rows / total rows = 1/1
+---------+-----------+
| cbool | cstring |
|---------+-----------|
| 1 | 1 |
+---------+-----------+
Cast to date example:
os> source=people | eval `cdate` = CAST('2012-08-07' as date), `ctime` = CAST('01:01:01' as time), `ctimestamp` = CAST('2012-08-07 01:01:01' as timestamp) | fields `cdate`, `ctime`, `ctimestamp`
fetched rows / total rows = 1/1
+------------+----------+---------------------+
| cdate | ctime | ctimestamp |
|------------+----------+---------------------|
| 2012-08-07 | 01:01:01 | 2012-08-07 01:01:01 |
+------------+----------+---------------------+
Cast function can be chained:
os> source=people | eval `cbool` = CAST(CAST(true as string) as boolean) | fields `cbool`
fetched rows / total rows = 1/1
+---------+
| cbool |
|---------|
| True |
+---------+