spark_read_parquet
Read a Parquet file into a Spark DataFrame
Read a Parquet file into a Spark DataFrame.
Usage
spark_read_parquet(sc, name, path, options = list(), repartition = 0,
memory = TRUE, overwrite = TRUE, columns = NULL, ...)Arguments
- sc
A
spark_connection.- name
The name to assign to the newly generated table.
- path
The path to the file. Needs to be accessible from the cluster. Supports the "hdfs://", "s3n://" and "file://" protocols.
- options
A list of strings with additional options. See http://spark.apache.org/docs/latest/sql-programming-guide.html#configuration.
- repartition
The number of partitions used to distribute the generated table. Use 0 (the default) to avoid partitioning.
- memory
Boolean; should the data be loaded eagerly into memory? (That is, should the table be cached?)
- overwrite
Boolean; overwrite the table with the given name if it already exists?
- columns
A vector of column names or a named vector of column types.
- ...
Optional arguments; currently unused.
Details
You can read data from HDFS (hdfs://), S3 (s3n://), as well as
the local file system (file://).
If you are reading from a secure S3 bucket be sure that the AWS_ACCESS_KEY_ID and
AWS_SECRET_ACCESS_KEY environment variables are both defined.
See Also
Other Spark serialization routines: spark_load_table,
spark_read_csv,
spark_read_jdbc,
spark_read_json,
spark_read_source,
spark_read_table,
spark_save_table,
spark_write_csv,
spark_write_jdbc,
spark_write_json,
spark_write_parquet,
spark_write_source,
spark_write_table