问题
Below are the last 2 lines of the PySpark ETL code:
df_writer = DataFrameWriter(usage_fact)
df_writer.partitionBy("data_date", "data_product").saveAsTable(usageWideFactTable, format=fileFormat,mode=writeMode,path=usageWideFactpath)
Where, WriteMode= append and fileFormat=orc
I wanted to use insert overwrite in place of this so that my data is not getting appended when I re-run the code. Hence I have used this:
usage_fact.createOrReplaceTempView("usage_fact")
fact = spark.sql("insert overwrite table " + usageWideFactTable + " partition (data_date, data_product) select * from usage_fact")
But this is giving me below error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/spark/python/pyspark/sql/session.py", line 545, in sql
return DataFrame(self._jsparkSession.sql(sqlQuery), self._wrapped)
File "/usr/lib/spark/python/lib/py4j-0.10.4-src.zip/py4j/java_gateway.py", line 1133, in __call__
File "/usr/lib/spark/python/pyspark/sql/utils.py", line 69, in deco
raise AnalysisException(s.split(': ', 1)[1], stackTrace)
pyspark.sql.utils.AnalysisException: u'Cannot overwrite a path that is also being read from.;'
Looks like I cannot overwrite a path from where I am reading from but don't know how to rectify it as I am new to PySpark. What exact code I should use so that this issue is removed?
回答1:
It worked for me with same above code. I just made change in the DDL and recreated the table with below details: (Removed Properties, if used)
PARTITIONED BY (
`data_date` string,
`data_product` string)
ROW FORMAT SERDE
'org.apache.hadoop.hive.ql.io.orc.OrcSerde'
WITH SERDEPROPERTIES (
'path'='s3://saasdata/datawarehouse/fact/UsageFact/')
STORED AS INPUTFORMAT
'org.apache.hadoop.hive.ql.io.orc.OrcInputFormat'
OUTPUTFORMAT
'org.apache.hadoop.hive.ql.io.orc.OrcOutputFormat'
LOCATION
's3://saasdata/datawarehouse/fact/UsageFact/'
来源：https://stackoverflow.com/questions/49920983/pyspark-insert-overwrite-issue