Hive嵌入Python
Python的输入输出都是\t为分隔符，否则会出错，python脚本输入print出规定格式的数据
用法为先add file，使用语法为TRANSFORM (name, items) USING ‘python test.py‘ AS (name string, item1 string,item2 string,item3 string)，这里后面几个字段对应python的类型
下面是一个将一列转成多列表小案例：
create table test (name string,items string) ROW FORMAT DELIMITED FIELDS TERMINATED BY ‘\t‘;
LOAD DATA local INPATH ‘/opt/data/tt.txt‘ OVERWRITE INTO TABLE test ;
tt.txt的内容：
tom shu fa,wei qi,chang ge jack game,kan shu,shang wang lusi lv you,guang jie,gou wu
表2：
create table test2 (name string,item1 string,item2 string,item3 string) ROW FORMAT DELIMITED FIELDS TERMINATED BY ‘\t‘;
-- 将python脚本上传到Hive Hive> add file /root/test.py
-- 将结果放到test2中 INSERT OVERWRITE TABLE test2 SELECT TRANSFORM (name, items) USING ‘python test.py‘ AS (name string, item1 string,item2 string,item3 string) FROM test;
#!/usr/bin/python import sys for line in sys.stdin: line = line.strip() name,it = line.split(‘\t‘) count = it.count(‘,‘)+1 for i in range(0,3-count): it = it+‘,NULL‘ result = it.split(‘,‘)[0:3] print ‘%s\t%s‘%(name,‘\t‘.join(result))
结果：
-- 表1 hive> select * from test; OK tom shu fa,wei qi,chang ge jack game,kan shu,shang wang lusi lv you,guang jie,gou wu Time taken: 0.07 seconds, Fetched: 3 row(s)
hive> desc test2;
OK
name string
item1 string
item2 string
item3 string
Time taken: 0.141 seconds, Fetched: 4 row(s)
-- 表2 hive> select * from test2; OK tom shu fa wei qi chang ge jack game kan shu shang wang lusi lv you guang jie gou wu Time taken: 1.368 seconds, Fetched: 3 row(s)
原文：http://www.cnblogs.com/raphael5200/p/5221927.html