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# # Licensed to the Apache Software Foundation (ASF) under one or more # contributor license agreements. See the NOTICE file distributed with # this work for additional information regarding copyright ownership. # The ASF licenses this file to You under the Apache License, Version 2.0 # (the "License"); you may not use this file except in compliance with # the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. #
""" Set named options (filter out those the value is None) """
""" Interface used to load a :class:`DataFrame` from external storage systems (e.g. file systems, key-value stores, etc). Use :attr:`SparkSession.read` to access this.
.. versionadded:: 1.4 """
"""Specifies the input data source format.
.. versionadded:: 1.4.0
Parameters ---------- source : str string, name of the data source, e.g. 'json', 'parquet'.
Examples -------- >>> df = spark.read.format('json').load('python/test_support/sql/people.json') >>> df.dtypes [('age', 'bigint'), ('name', 'string')]
"""
"""Specifies the input schema.
Some data sources (e.g. JSON) can infer the input schema automatically from data. By specifying the schema here, the underlying data source can skip the schema inference step, and thus speed up data loading.
.. versionadded:: 1.4.0
Parameters ---------- schema : :class:`pyspark.sql.types.StructType` or str a :class:`pyspark.sql.types.StructType` object or a DDL-formatted string (For example ``col0 INT, col1 DOUBLE``).
>>> s = spark.read.schema("col0 INT, col1 DOUBLE") """ else: raise TypeError("schema should be StructType or string")
def option(self, key, value): """Adds an input option for the underlying data source. """
def options(self, **options): """Adds input options for the underlying data source. """
"""Loads data from a data source and returns it as a :class:`DataFrame`.
.. versionadded:: 1.4.0
Parameters ---------- path : str or list, optional optional string or a list of string for file-system backed data sources. format : str, optional optional string for format of the data source. Default to 'parquet'. schema : :class:`pyspark.sql.types.StructType` or str, optional optional :class:`pyspark.sql.types.StructType` for the input schema or a DDL-formatted string (For example ``col0 INT, col1 DOUBLE``). **options : dict all other string options
Examples -------- >>> df = spark.read.format("parquet").load('python/test_support/sql/parquet_partitioned', ... opt1=True, opt2=1, opt3='str') >>> df.dtypes [('name', 'string'), ('year', 'int'), ('month', 'int'), ('day', 'int')]
>>> df = spark.read.format('json').load(['python/test_support/sql/people.json', ... 'python/test_support/sql/people1.json']) >>> df.dtypes [('age', 'bigint'), ('aka', 'string'), ('name', 'string')] """ self.schema(schema) path = [path] else:
allowComments=None, allowUnquotedFieldNames=None, allowSingleQuotes=None, allowNumericLeadingZero=None, allowBackslashEscapingAnyCharacter=None, mode=None, columnNameOfCorruptRecord=None, dateFormat=None, timestampFormat=None, multiLine=None, allowUnquotedControlChars=None, lineSep=None, samplingRatio=None, dropFieldIfAllNull=None, encoding=None, locale=None, pathGlobFilter=None, recursiveFileLookup=None, allowNonNumericNumbers=None, modifiedBefore=None, modifiedAfter=None): """ Loads JSON files and returns the results as a :class:`DataFrame`.
`JSON Lines <http://jsonlines.org/>`_ (newline-delimited JSON) is supported by default. For JSON (one record per file), set the ``multiLine`` parameter to ``true``.
If the ``schema`` parameter is not specified, this function goes through the input once to determine the input schema.
.. versionadded:: 1.4.0
Parameters ---------- path : str, list or :class:`RDD` string represents path to the JSON dataset, or a list of paths, or RDD of Strings storing JSON objects. schema : :class:`pyspark.sql.types.StructType` or str, optional an optional :class:`pyspark.sql.types.StructType` for the input schema or a DDL-formatted string (For example ``col0 INT, col1 DOUBLE``).
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-json.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df1 = spark.read.json('python/test_support/sql/people.json') >>> df1.dtypes [('age', 'bigint'), ('name', 'string')] >>> rdd = sc.textFile('python/test_support/sql/people.json') >>> df2 = spark.read.json(rdd) >>> df2.dtypes [('age', 'bigint'), ('name', 'string')]
""" schema=schema, primitivesAsString=primitivesAsString, prefersDecimal=prefersDecimal, allowComments=allowComments, allowUnquotedFieldNames=allowUnquotedFieldNames, allowSingleQuotes=allowSingleQuotes, allowNumericLeadingZero=allowNumericLeadingZero, allowBackslashEscapingAnyCharacter=allowBackslashEscapingAnyCharacter, mode=mode, columnNameOfCorruptRecord=columnNameOfCorruptRecord, dateFormat=dateFormat, timestampFormat=timestampFormat, multiLine=multiLine, allowUnquotedControlChars=allowUnquotedControlChars, lineSep=lineSep, samplingRatio=samplingRatio, dropFieldIfAllNull=dropFieldIfAllNull, encoding=encoding, locale=locale, pathGlobFilter=pathGlobFilter, recursiveFileLookup=recursiveFileLookup, modifiedBefore=modifiedBefore, modifiedAfter=modifiedAfter, allowNonNumericNumbers=allowNonNumericNumbers) else: raise TypeError("path can be only string, list or RDD")
"""Returns the specified table as a :class:`DataFrame`.
.. versionadded:: 1.4.0
Parameters ---------- tableName : str string, name of the table.
Examples -------- >>> df = spark.read.parquet('python/test_support/sql/parquet_partitioned') >>> df.createOrReplaceTempView('tmpTable') >>> spark.read.table('tmpTable').dtypes [('name', 'string'), ('year', 'int'), ('month', 'int'), ('day', 'int')] """
""" Loads Parquet files, returning the result as a :class:`DataFrame`.
.. versionadded:: 1.4.0
Parameters ---------- paths : str
Other Parameters ---------------- **options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-parquet.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df = spark.read.parquet('python/test_support/sql/parquet_partitioned') >>> df.dtypes [('name', 'string'), ('year', 'int'), ('month', 'int'), ('day', 'int')] """ recursiveFileLookup=recursiveFileLookup, modifiedBefore=modifiedBefore, modifiedAfter=modifiedAfter, datetimeRebaseMode=datetimeRebaseMode, int96RebaseMode=int96RebaseMode)
recursiveFileLookup=None, modifiedBefore=None, modifiedAfter=None): """ Loads text files and returns a :class:`DataFrame` whose schema starts with a string column named "value", and followed by partitioned columns if there are any. The text files must be encoded as UTF-8.
By default, each line in the text file is a new row in the resulting DataFrame.
.. versionadded:: 1.6.0
Parameters ---------- paths : str or list string, or list of strings, for input path(s).
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-text.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df = spark.read.text('python/test_support/sql/text-test.txt') >>> df.collect() [Row(value='hello'), Row(value='this')] >>> df = spark.read.text('python/test_support/sql/text-test.txt', wholetext=True) >>> df.collect() [Row(value='hello\\nthis')] """ wholetext=wholetext, lineSep=lineSep, pathGlobFilter=pathGlobFilter, recursiveFileLookup=recursiveFileLookup, modifiedBefore=modifiedBefore, modifiedAfter=modifiedAfter)
comment=None, header=None, inferSchema=None, ignoreLeadingWhiteSpace=None, ignoreTrailingWhiteSpace=None, nullValue=None, nanValue=None, positiveInf=None, negativeInf=None, dateFormat=None, timestampFormat=None, maxColumns=None, maxCharsPerColumn=None, maxMalformedLogPerPartition=None, mode=None, columnNameOfCorruptRecord=None, multiLine=None, charToEscapeQuoteEscaping=None, samplingRatio=None, enforceSchema=None, emptyValue=None, locale=None, lineSep=None, pathGlobFilter=None, recursiveFileLookup=None, modifiedBefore=None, modifiedAfter=None, unescapedQuoteHandling=None): r"""Loads a CSV file and returns the result as a :class:`DataFrame`.
This function will go through the input once to determine the input schema if ``inferSchema`` is enabled. To avoid going through the entire data once, disable ``inferSchema`` option or specify the schema explicitly using ``schema``.
.. versionadded:: 2.0.0
Parameters ---------- path : str or list string, or list of strings, for input path(s), or RDD of Strings storing CSV rows. schema : :class:`pyspark.sql.types.StructType` or str, optional an optional :class:`pyspark.sql.types.StructType` for the input schema or a DDL-formatted string (For example ``col0 INT, col1 DOUBLE``).
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-csv.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df = spark.read.csv('python/test_support/sql/ages.csv') >>> df.dtypes [('_c0', 'string'), ('_c1', 'string')] >>> rdd = sc.textFile('python/test_support/sql/ages.csv') >>> df2 = spark.read.csv(rdd) >>> df2.dtypes [('_c0', 'string'), ('_c1', 'string')] """ schema=schema, sep=sep, encoding=encoding, quote=quote, escape=escape, comment=comment, header=header, inferSchema=inferSchema, ignoreLeadingWhiteSpace=ignoreLeadingWhiteSpace, ignoreTrailingWhiteSpace=ignoreTrailingWhiteSpace, nullValue=nullValue, nanValue=nanValue, positiveInf=positiveInf, negativeInf=negativeInf, dateFormat=dateFormat, timestampFormat=timestampFormat, maxColumns=maxColumns, maxCharsPerColumn=maxCharsPerColumn, maxMalformedLogPerPartition=maxMalformedLogPerPartition, mode=mode, columnNameOfCorruptRecord=columnNameOfCorruptRecord, multiLine=multiLine, charToEscapeQuoteEscaping=charToEscapeQuoteEscaping, samplingRatio=samplingRatio, enforceSchema=enforceSchema, emptyValue=emptyValue, locale=locale, lineSep=lineSep, pathGlobFilter=pathGlobFilter, recursiveFileLookup=recursiveFileLookup, modifiedBefore=modifiedBefore, modifiedAfter=modifiedAfter, unescapedQuoteHandling=unescapedQuoteHandling) x = str(x) # see SPARK-22112 # There aren't any jvm api for creating a dataframe from rdd storing csv. # We can do it through creating a jvm dataset firstly and using the jvm api # for creating a dataframe from dataset storing csv. jrdd.rdd(), self._spark._jvm.Encoders.STRING()) else: raise TypeError("path can be only string, list or RDD")
modifiedBefore=None, modifiedAfter=None): """Loads ORC files, returning the result as a :class:`DataFrame`.
.. versionadded:: 1.5.0
Parameters ---------- path : str or list
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-orc.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df = spark.read.orc('python/test_support/sql/orc_partitioned') >>> df.dtypes [('a', 'bigint'), ('b', 'int'), ('c', 'int')] """ modifiedBefore=modifiedBefore, modifiedAfter=modifiedAfter, recursiveFileLookup=recursiveFileLookup)
predicates=None, properties=None): """ Construct a :class:`DataFrame` representing the database table named ``table`` accessible via JDBC URL ``url`` and connection ``properties``.
Partitions of the table will be retrieved in parallel if either ``column`` or ``predicates`` is specified. ``lowerBound``, ``upperBound`` and ``numPartitions`` is needed when ``column`` is specified.
If both ``column`` and ``predicates`` are specified, ``column`` will be used.
.. versionadded:: 1.4.0
Parameters ---------- table : str the name of the table column : str, optional alias of ``partitionColumn`` option. Refer to ``partitionColumn`` in `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-jdbc.html#data-source-option>`_ in the version you use. predicates : list, optional a list of expressions suitable for inclusion in WHERE clauses; each one defines one partition of the :class:`DataFrame` properties : dict, optional a dictionary of JDBC database connection arguments. Normally at least properties "user" and "password" with their corresponding values. For example { 'user' : 'SYSTEM', 'password' : 'mypassword' }
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-jdbc.html#data-source-option>`_ in the version you use.
.. # noqa
Notes ----- Don't create too many partitions in parallel on a large cluster; otherwise Spark might crash your external database systems.
Returns ------- :class:`DataFrame` """ if properties is None: properties = dict() jprop = JavaClass("java.util.Properties", self._spark._sc._gateway._gateway_client)() for k in properties: jprop.setProperty(k, properties[k]) if column is not None: assert lowerBound is not None, "lowerBound can not be None when ``column`` is specified" assert upperBound is not None, "upperBound can not be None when ``column`` is specified" assert numPartitions is not None, \ "numPartitions can not be None when ``column`` is specified" return self._df(self._jreader.jdbc(url, table, column, int(lowerBound), int(upperBound), int(numPartitions), jprop)) if predicates is not None: gateway = self._spark._sc._gateway jpredicates = utils.toJArray(gateway, gateway.jvm.java.lang.String, predicates) return self._df(self._jreader.jdbc(url, table, jpredicates, jprop)) return self._df(self._jreader.jdbc(url, table, jprop))
""" Interface used to write a :class:`DataFrame` to external storage systems (e.g. file systems, key-value stores, etc). Use :attr:`DataFrame.write` to access this.
.. versionadded:: 1.4 """
from pyspark.sql.streaming import StreamingQuery return StreamingQuery(jsq)
"""Specifies the behavior when data or table already exists.
Options include:
* `append`: Append contents of this :class:`DataFrame` to existing data. * `overwrite`: Overwrite existing data. * `error` or `errorifexists`: Throw an exception if data already exists. * `ignore`: Silently ignore this operation if data already exists.
.. versionadded:: 1.4.0
Examples -------- >>> df.write.mode('append').parquet(os.path.join(tempfile.mkdtemp(), 'data')) """ # At the JVM side, the default value of mode is already set to "error". # So, if the given saveMode is None, we will not call JVM-side's mode method.
"""Specifies the underlying output data source.
.. versionadded:: 1.4.0
Parameters ---------- source : str string, name of the data source, e.g. 'json', 'parquet'.
Examples -------- >>> df.write.format('json').save(os.path.join(tempfile.mkdtemp(), 'data')) """
def option(self, key, value): """Adds an output option for the underlying data source. """
def options(self, **options): """Adds output options for the underlying data source. """
"""Partitions the output by the given columns on the file system.
If specified, the output is laid out on the file system similar to Hive's partitioning scheme.
.. versionadded:: 1.4.0
Parameters ---------- cols : str or list name of columns
Examples -------- >>> df.write.partitionBy('year', 'month').parquet(os.path.join(tempfile.mkdtemp(), 'data')) """ cols = cols[0]
"""Buckets the output by the given columns. If specified, the output is laid out on the file system similar to Hive's bucketing scheme, but with a different bucket hash function and is not compatible with Hive's bucketing.
.. versionadded:: 2.3.0
Parameters ---------- numBuckets : int the number of buckets to save col : str, list or tuple a name of a column, or a list of names. cols : str additional names (optional). If `col` is a list it should be empty.
Notes ----- Applicable for file-based data sources in combination with :py:meth:`DataFrameWriter.saveAsTable`.
Examples -------- >>> (df.write.format('parquet') # doctest: +SKIP ... .bucketBy(100, 'year', 'month') ... .mode("overwrite") ... .saveAsTable('bucketed_table')) """ raise TypeError("numBuckets should be an int, got {0}.".format(type(numBuckets)))
raise ValueError("col is a {0} but cols are not empty".format(type(col)))
raise TypeError("all names should be `str`")
"""Sorts the output in each bucket by the given columns on the file system.
.. versionadded:: 2.3.0
Parameters ---------- col : str, tuple or list a name of a column, or a list of names. cols : str additional names (optional). If `col` is a list it should be empty.
Examples -------- >>> (df.write.format('parquet') # doctest: +SKIP ... .bucketBy(100, 'year', 'month') ... .sortBy('day') ... .mode("overwrite") ... .saveAsTable('sorted_bucketed_table')) """ raise ValueError("col is a {0} but cols are not empty".format(type(col)))
raise TypeError("all names should be `str`")
"""Saves the contents of the :class:`DataFrame` to a data source.
The data source is specified by the ``format`` and a set of ``options``. If ``format`` is not specified, the default data source configured by ``spark.sql.sources.default`` will be used.
.. versionadded:: 1.4.0
Parameters ---------- path : str, optional the path in a Hadoop supported file system format : str, optional the format used to save mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists. partitionBy : list, optional names of partitioning columns **options : dict all other string options
Examples -------- >>> df.write.mode("append").save(os.path.join(tempfile.mkdtemp(), 'data')) """ self.partitionBy(partitionBy) self._jwrite.save() else:
"""Inserts the content of the :class:`DataFrame` to the specified table.
It requires that the schema of the :class:`DataFrame` is the same as the schema of the table.
Parameters ---------- overwrite : bool, optional If true, overwrites existing data. Disabled by default
Notes ----- Unlike :meth:`DataFrameWriter.saveAsTable`, :meth:`DataFrameWriter.insertInto` ignores the column names and just uses position-based resolution.
"""
"""Saves the content of the :class:`DataFrame` as the specified table.
In the case the table already exists, behavior of this function depends on the save mode, specified by the `mode` function (default to throwing an exception). When `mode` is `Overwrite`, the schema of the :class:`DataFrame` does not need to be the same as that of the existing table.
* `append`: Append contents of this :class:`DataFrame` to existing data. * `overwrite`: Overwrite existing data. * `error` or `errorifexists`: Throw an exception if data already exists. * `ignore`: Silently ignore this operation if data already exists.
.. versionadded:: 1.4.0
Notes ----- When `mode` is `Append`, if there is an existing table, we will use the format and options of the existing table. The column order in the schema of the :class:`DataFrame` doesn't need to be same as that of the existing table. Unlike :meth:`DataFrameWriter.insertInto`, :meth:`DataFrameWriter.saveAsTable` will use the column names to find the correct column positions.
Parameters ---------- name : str the table name format : str, optional the format used to save mode : str, optional one of `append`, `overwrite`, `error`, `errorifexists`, `ignore` \ (default: error) partitionBy : str or list names of partitioning columns **options : dict all other string options """ self.partitionBy(partitionBy)
lineSep=None, encoding=None, ignoreNullFields=None): """Saves the content of the :class:`DataFrame` in JSON format (`JSON Lines text format or newline-delimited JSON <http://jsonlines.org/>`_) at the specified path.
.. versionadded:: 1.4.0
Parameters ---------- path : str the path in any Hadoop supported file system mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists.
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-json.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df.write.json(os.path.join(tempfile.mkdtemp(), 'data')) """ compression=compression, dateFormat=dateFormat, timestampFormat=timestampFormat, lineSep=lineSep, encoding=encoding, ignoreNullFields=ignoreNullFields)
"""Saves the content of the :class:`DataFrame` in Parquet format at the specified path.
.. versionadded:: 1.4.0
Parameters ---------- path : str the path in any Hadoop supported file system mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists. partitionBy : str or list, optional names of partitioning columns
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-parquet.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df.write.parquet(os.path.join(tempfile.mkdtemp(), 'data')) """ self.partitionBy(partitionBy)
"""Saves the content of the DataFrame in a text file at the specified path. The text files will be encoded as UTF-8.
.. versionadded:: 1.6.0
Parameters ---------- path : str the path in any Hadoop supported file system
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-text.html#data-source-option>`_ in the version you use.
.. # noqa
The DataFrame must have only one column that is of string type. Each row becomes a new line in the output file. """
header=None, nullValue=None, escapeQuotes=None, quoteAll=None, dateFormat=None, timestampFormat=None, ignoreLeadingWhiteSpace=None, ignoreTrailingWhiteSpace=None, charToEscapeQuoteEscaping=None, encoding=None, emptyValue=None, lineSep=None): r"""Saves the content of the :class:`DataFrame` in CSV format at the specified path.
.. versionadded:: 2.0.0
Parameters ---------- path : str the path in any Hadoop supported file system mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists.
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-csv.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> df.write.csv(os.path.join(tempfile.mkdtemp(), 'data')) """ nullValue=nullValue, escapeQuotes=escapeQuotes, quoteAll=quoteAll, dateFormat=dateFormat, timestampFormat=timestampFormat, ignoreLeadingWhiteSpace=ignoreLeadingWhiteSpace, ignoreTrailingWhiteSpace=ignoreTrailingWhiteSpace, charToEscapeQuoteEscaping=charToEscapeQuoteEscaping, encoding=encoding, emptyValue=emptyValue, lineSep=lineSep)
"""Saves the content of the :class:`DataFrame` in ORC format at the specified path.
.. versionadded:: 1.5.0
Parameters ---------- path : str the path in any Hadoop supported file system mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists. partitionBy : str or list, optional names of partitioning columns
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-orc.html#data-source-option>`_ in the version you use.
.. # noqa
Examples -------- >>> orc_df = spark.read.orc('python/test_support/sql/orc_partitioned') >>> orc_df.write.orc(os.path.join(tempfile.mkdtemp(), 'data')) """ self.partitionBy(partitionBy)
"""Saves the content of the :class:`DataFrame` to an external database table via JDBC.
.. versionadded:: 1.4.0
Parameters ---------- table : str Name of the table in the external database. mode : str, optional specifies the behavior of the save operation when data already exists.
* ``append``: Append contents of this :class:`DataFrame` to existing data. * ``overwrite``: Overwrite existing data. * ``ignore``: Silently ignore this operation if data already exists. * ``error`` or ``errorifexists`` (default case): Throw an exception if data already \ exists. properties : dict a dictionary of JDBC database connection arguments. Normally at least properties "user" and "password" with their corresponding values. For example { 'user' : 'SYSTEM', 'password' : 'mypassword' }
Other Parameters ---------------- Extra options For the extra options, refer to `Data Source Option <https://spark.apache.org/docs/latest/sql-data-sources-jdbc.html#data-source-option>`_ in the version you use.
.. # noqa
Notes ----- Don't create too many partitions in parallel on a large cluster; otherwise Spark might crash your external database systems. """ if properties is None: properties = dict() jprop = JavaClass("java.util.Properties", self._spark._sc._gateway._gateway_client)() for k in properties: jprop.setProperty(k, properties[k]) self.mode(mode)._jwrite.jdbc(url, table, jprop)
""" Interface used to write a class:`pyspark.sql.dataframe.DataFrame` to external storage using the v2 API.
.. versionadded:: 3.1.0 """
def using(self, provider): """ Specifies a provider for the underlying output data source. Spark's default catalog supports "parquet", "json", etc. """
def option(self, key, value): """ Add a write option. """
def options(self, **options): """ Add write options. """
def tableProperty(self, property, value): """ Add table property. """
def partitionedBy(self, col, *cols): """ Partition the output table created by `create`, `createOrReplace`, or `replace` using the given columns or transforms.
When specified, the table data will be stored by these values for efficient reads.
For example, when a table is partitioned by day, it may be stored in a directory layout like:
* `table/day=2019-06-01/` * `table/day=2019-06-02/`
Partitioning is one of the most widely used techniques to optimize physical data layout. It provides a coarse-grained index for skipping unnecessary data reads when queries have predicates on the partitioned columns. In order for partitioning to work well, the number of distinct values in each column should typically be less than tens of thousands.
`col` and `cols` support only the following functions:
* :py:func:`pyspark.sql.functions.years` * :py:func:`pyspark.sql.functions.months` * :py:func:`pyspark.sql.functions.days` * :py:func:`pyspark.sql.functions.hours` * :py:func:`pyspark.sql.functions.bucket`
"""
def create(self): """ Create a new table from the contents of the data frame.
The new table's schema, partition layout, properties, and other configuration will be based on the configuration set on this writer. """ self._jwriter.create()
def replace(self): """ Replace an existing table with the contents of the data frame.
The existing table's schema, partition layout, properties, and other configuration will be replaced with the contents of the data frame and the configuration set on this writer. """ self._jwriter.replace()
def createOrReplace(self): """ Create a new table or replace an existing table with the contents of the data frame.
The output table's schema, partition layout, properties, and other configuration will be based on the contents of the data frame and the configuration set on this writer. If the table exists, its configuration and data will be replaced. """ self._jwriter.createOrReplace()
def append(self): """ Append the contents of the data frame to the output table. """ self._jwriter.append()
def overwrite(self, condition): """ Overwrite rows matching the given filter condition with the contents of the data frame in the output table. """ self._jwriter.overwrite(condition)
def overwritePartitions(self): """ Overwrite all partition for which the data frame contains at least one row with the contents of the data frame in the output table.
This operation is equivalent to Hive's `INSERT OVERWRITE ... PARTITION`, which replaces partitions dynamically depending on the contents of the data frame. """ self._jwriter.overwritePartitions()
except py4j.protocol.Py4JError: spark = SparkSession(sc)
pyspark.sql.readwriter, globs=globs, optionflags=doctest.ELLIPSIS | doctest.NORMALIZE_WHITESPACE | doctest.REPORT_NDIFF) sys.exit(-1)
|