[HIVE]hive中生成从1到n的连续数字的transform或map方法
(2011-08-12 19:56:57)
标签:
hivemapreducetransform连续数字序列杂谈 |
分类: Hadoop Hive |
ORACLE中生成从1到n的连续数字的方法很多,最简单的一种是:
LEVEL
1
2
3
4
5
try:
for line in sys.stdin:
n = line.strip()
for i in range(int(n)):
print
i+1
except:
return None
main()
ETL@RACTEST> select level from dual connect by
level<=5;
----------
我用python写了一个很简单的小程序,可以借助hive的transform语句实现一样的功能:
hive> select transform(5) using 'serial.py' as
rn from dual;
OK
1
2
3
4
5
也可以使用MAP:
hive> map 5 using 'serial.py' as rn from
dual;
OK
1
2
3
4
5
提供一下python代码,仅供参考:
#!/usr/bin/env python
'''This is a python script to generate value from 1 to
n'''
import sys
def main():
if __name__ == "__main__":