Overwrite only some partitions in a partitioned spark Dataset
Just FYI, for PySpark users make sure to set overwrite=True
in the insertInto
otherwise the mode would be changed to append
from the source code:
def insertInto(self, tableName, overwrite=False):
self._jwrite.mode(
"overwrite" if overwrite else "append"
).insertInto(tableName)
this how to use it:
spark.conf.set("spark.sql.sources.partitionOverwriteMode","DYNAMIC")
data.write.insertInto("partitioned_table", overwrite=True)
or in the SQL version works fine.
INSERT OVERWRITE TABLE [db_name.]table_name [PARTITION part_spec] select_statement
for doc look at here
Since Spark 2.3.0 this is an option when overwriting a table. To overwrite it, you need to set the new spark.sql.sources.partitionOverwriteMode
setting to dynamic
, the dataset needs to be partitioned, and the write mode overwrite
.
Example in scala:
spark.conf.set(
"spark.sql.sources.partitionOverwriteMode", "dynamic"
)
data.write.mode("overwrite").insertInto("partitioned_table")
I recommend doing a repartition based on your partition column before writing, so you won't end up with 400 files per folder.
Before Spark 2.3.0, the best solution would be to launch SQL statements to delete those partitions and then write them with mode append.