class SparkHiveDataSet(AbstractDataSet[
SparkHiveDataSet loads and saves Spark dataframes stored on Hive. This data set also handles some incompatible file types such as using partitioned parquet on hive which will not normally allow upserts to existing data without a complete replacement of the existing file/partition.
This DataSet has some key assumptions:
- Schemas do not change during the pipeline run (defined PKs must be present for the duration of the pipeline)
- Tables are not being externally modified during upserts. The upsert method is NOT ATOMIC
to external changes to the target table while executing. Upsert methodology works by leveraging Spark DataFrame execution plan checkpointing.
Example usage for the YAML API:
hive_dataset:
type: spark.SparkHiveDataSet
database: hive_database
table: table_name
write_mode: overwrite
Example usage for the Python API:
>>> from pyspark.sql import SparkSession >>> from pyspark.sql.types import (StructField, StringType, >>> IntegerType, StructType) >>> >>> from kedro.extras.datasets.spark import SparkHiveDataSet >>> >>> schema = StructType([StructField("name", StringType(), True), >>> StructField("age", IntegerType(), True)]) >>> >>> data = [('Alex', 31), ('Bob', 12), ('Clarke', 65), ('Dave', 29)] >>> >>> spark_df = SparkSession.builder.getOrCreate().createDataFrame(data, schema) >>> >>> data_set = SparkHiveDataSet(database="test_database", table="test_table", >>> write_mode="overwrite") >>> data_set.save(spark_df) >>> reloaded = data_set.load() >>> >>> reloaded.take(4)
Method | __getstate__ |
Undocumented |
Method | __init__ |
Creates a new instance of SparkHiveDataSet. |
Constant | DEFAULT |
Undocumented |
Static Method | _get |
This method should only be used to get an existing SparkSession with valid Hive configuration. Configuration for Hive is read from hive-site.xml on the classpath. It supports running both SQL and HiveQL commands... |
Method | _create |
Undocumented |
Method | _describe |
Undocumented |
Method | _exists |
Undocumented |
Method | _load |
Undocumented |
Method | _save |
Undocumented |
Method | _upsert |
Undocumented |
Method | _validate |
Undocumented |
Instance Variable | _database |
Undocumented |
Instance Variable | _eager |
Undocumented |
Instance Variable | _format |
Undocumented |
Instance Variable | _full |
Undocumented |
Instance Variable | _save |
Undocumented |
Instance Variable | _table |
Undocumented |
Instance Variable | _table |
Undocumented |
Instance Variable | _write |
Undocumented |
Inherited from AbstractDataSet
:
Class Method | from |
Create a data set instance using the configuration provided. |
Method | __str__ |
Undocumented |
Method | exists |
Checks whether a data set's output already exists by calling the provided _exists() method. |
Method | load |
Loads data by delegation to the provided load method. |
Method | release |
Release any cached data. |
Method | save |
Saves data by delegation to the provided save method. |
Method | _copy |
Undocumented |
Method | _release |
Undocumented |
Property | _logger |
Undocumented |
str
, table: str
, write_mode: str
= 'errorifexists', table_pk: List[ str]
= None, save_args: Dict[ str, Any]
= None):
(source)
¶
Creates a new instance of SparkHiveDataSet.
Note
For users leveraging the upsert
functionality,
a checkpoint
directory must be set, e.g. using
spark.sparkContext.setCheckpointDir("/path/to/dir")
or directly in the Spark conf folder.
Parameters | |
database:str | The name of the hive database. |
table:str | The name of the table within the database. |
writestr | insert, upsert or overwrite are supported. |
tableList[ | If performing an upsert, this identifies the primary key columns used to resolve preexisting data. Is required for write_mode="upsert". |
saveDict[ | Optional mapping of any options,
passed to the DataFrameWriter.saveAsTable as kwargs.
Key example of this is partitionBy which allows data partitioning
on a list of column names.
Other HiveOptions can be found here:
https://spark.apache.org/docs/latest/sql-data-sources-hive-tables.html#specifying-storage-format-for-hive-tables |
Raises | |
DataSetError | Invalid configuration supplied |
This method should only be used to get an existing SparkSession
with valid Hive configuration.
Configuration for Hive is read from hive-site.xml on the classpath.
It supports running both SQL and HiveQL commands.
Additionally, if users are leveraging the upsert
functionality,
then a checkpoint
directory must be set, e.g. using
spark.sparkContext.setCheckpointDir("/path/to/dir")