我是新手,通过POC激发和学习。作为这个POC的一部分,我试图直接执行具有transform关键字的hql文件以使用python udf。
我在CLI中测试了hql脚本" hive -f filename.hql"它工作正常。 我在spark-sql中尝试过相同的脚本,但是找不到hdfs path not error错误。我尝试以不同的方式提供hdfs路径,如下所示,但都没有工作
"/test/scripts/test.hql"
"hdfs://test.net:8020/test/scripts/test.hql"
"hdfs:///test.net:8020/test/scripts/test.hql"
还尝试在hive转换代码中给出完整路径,如下所示
USING "scl enable python27 'python hdfs://test.net:8020/user/test/scripts/TestPython.py'"
Hive代码
add file hdfs://test.net:8020/user/test/scripts/TestPython.py;
select * from
(select transform (*)
USING "scl enable python27 'python TestPython.py'"
as (Col_1 STRING,
col_2 STRING,
...
..
col_125 STRING
)
FROM
test.transform_inner_temp1 a) b;
TestPython代码:
#!/usr/bin/env python
'''
Created on June 2, 2017
@author: test
'''
import sys
from datetime import datetime
import decimal
import string
D = decimal.Decimal
for line in sys.stdin:
line = sys.stdin.readline()
TempList = line.strip().split('\t')
col_1 = TempList[0]
...
....
col_125 = TempList[34] + TempList[32]
outList.extend((col_1,....col_125))
outValue = "\t".join(map(str,outList))
print "%s"%(outValue)
所以我尝试了另一种方法,直接在spark-submit
中执行spark-submit --master yarn-cluster hdfs://test.net:8020/user/test/scripts/testspark.py
testspark.py
from pyspark.sql.types import StringType
from pyspark import SparkConf, SparkContext
from pyspark import SQLContext
conf = SparkConf().setAppName("gveeran pyspark test")
sc = SparkContext(conf=conf)
sqlContext = SQLContext(sc)
with open("hdfs://test.net:8020/user/test/scripts/test.hql") as fr:
query = fr.read()
results = sqlContext.sql(query)
results.show()
但同样的问题如下
Traceback (most recent call last):
File "PySparkTest2.py", line 7, in <module>
with open("hdfs://test.net:8020/user/test/scripts/test.hql") as fr:
IOError: [Errno 2] No such file or directory: 'hdfs://test.net:8020/user/test/scripts/test.hql'
答案 0 :(得分:0)
您可以将文件作为查询读取,然后作为spark sql
作业执行
示例:-
from pyspark.sql import SparkSession
from pyspark.sql import SQLContext
sc =SparkContext.getOrCreate()
sqlCtx = SQLContext(sc)
with open("/home/hadoop/test/abc.hql") as fr:
query = fr.read()
print(query)
results = sqlCtx.sql(query)