cudf.DataFrame.to_parquet#

DataFrame.to_parquet(path, engine='cudf', compression='snappy', index=None, partition_cols=None, partition_file_name=None, partition_offsets=None, statistics='ROWGROUP', metadata_file_path=None, int96_timestamps=False, row_group_size_bytes=134217728, row_group_size_rows=None, max_page_size_bytes=None, max_page_size_rows=None, storage_options=None, return_metadata=False, use_dictionary=True, header_version='1.0', skip_compression=None, column_encoding=None, column_type_length=None, output_as_binary=None, *args, **kwargs)[source]#

Write a DataFrame to the parquet format.

Parameters:
pathstr or list of str

File path or Root Directory path. Will be used as Root Directory path while writing a partitioned dataset. Use list of str with partition_offsets to write parts of the dataframe to different files.

compression{‘snappy’, ‘ZSTD’, ‘LZ4’, None}, default ‘snappy’

Name of the compression to use; case insensitive. Use None for no compression.

indexbool, default None

If True, include the dataframe’s index(es) in the file output. If False, they will not be written to the file. If None, similar to True the dataframe’s index(es) will be saved, however, instead of being saved as values any RangeIndex will be stored as a range in the metadata so it doesn’t require much space and is faster. Other indexes will be included as columns in the file output.

partition_colslist, optional, default None

Column names by which to partition the dataset Columns are partitioned in the order they are given

partition_file_namestr, optional, default None

File name to use for partitioned datasets. Different partitions will be written to different directories, but all files will have this name. If nothing is specified, a random uuid4 hex string will be used for each file. This parameter is only supported by ‘cudf’ engine, and will be ignored by other engines.

partition_offsetslist, optional, default None

Offsets to partition the dataframe by. Should be used when path is list of str. Should be a list of integers of size len(path) + 1

statistics{‘ROWGROUP’, ‘PAGE’, ‘COLUMN’, ‘NONE’}, default ‘ROWGROUP’

Level at which column statistics should be included in file.

metadata_file_pathstr, optional, default None

If specified, this function will return a binary blob containing the footer metadata of the written parquet file. The returned blob will have the chunk.file_path field set to the metadata_file_path for each chunk. When using with partition_offsets, should be same size as len(path)

int96_timestampsbool, default False

If True, write timestamps in int96 format. This will convert timestamps from timestamp[ns], timestamp[ms], timestamp[s], and timestamp[us] to the int96 format, which is the number of Julian days and the number of nanoseconds since midnight of 1970-01-01. If False, timestamps will not be altered.

row_group_size_bytes: integer, default 134217728

Maximum size of each stripe of the output. If None, 134217728 (128.0 MB) will be used.

row_group_size_rows: integer or None, default None

Maximum number of rows of each stripe of the output. If None, 1000000 will be used.

max_page_size_bytes: integer or None, default None

Maximum uncompressed size of each page of the output. If None, 524288 (512KB) will be used.

max_page_size_rows: integer or None, default None

Maximum number of rows of each page of the output. If None, 20000 will be used.

max_dictionary_size: integer or None, default None

Maximum size of the dictionary page for each output column chunk. Dictionary encoding for column chunks that exceeds this limit will be disabled. If None, 1048576 (1MB) will be used.

storage_optionsdict, optional, default None

Extra options that make sense for a particular storage connection, e.g. host, port, username, password, etc. For HTTP(S) URLs the key-value pairs are forwarded to urllib.request.Request as header options. For other URLs (e.g. starting with “s3://”, and “gcs://”) the key-value pairs are forwarded to fsspec.open. Please see fsspec and urllib for more details.

return_metadatabool, default False

Return parquet metadata for written data. Returned metadata will include the file path metadata (relative to root_path). To request metadata binary blob when using with partition_cols, Pass return_metadata=True instead of specifying metadata_file_path

use_dictionarybool, default True

When False, prevents the use of dictionary encoding for Parquet page data. When True, dictionary encoding is preferred subject to max_dictionary_size constraints.

header_version{‘1.0’, ‘2.0’}, default “1.0”

Controls whether to use version 1.0 or version 2.0 page headers when encoding. Version 1.0 is more portable, but version 2.0 enables the use of newer encoding schemes.

force_nullable_schemabool, default False.

If True, writes all columns as null in schema. If False, columns are written as null if they contain null values, otherwise as not null.

skip_compressionset, optional, default None

If a column name is present in the set, that column will not be compressed, regardless of the compression setting.

column_encodingdict, optional, default None

Sets the page encoding to use on a per-column basis. The key is a column name, and the value is one of: ‘PLAIN’, ‘DICTIONARY’, ‘DELTA_BINARY_PACKED’, ‘DELTA_LENGTH_BYTE_ARRAY’, ‘DELTA_BYTE_ARRAY’, ‘BYTE_STREAM_SPLIT’, or ‘USE_DEFAULT’.

column_type_lengthdict, optional, default None

Specifies the width in bytes of FIXED_LEN_BYTE_ARRAY column elements. The key is a column name and the value is an integer. The named column will be output as unannotated binary (i.e. the column will behave as if output_as_binary was set).

output_as_binaryset, optional, default None

If a column name is present in the set, that column will be output as unannotated binary, rather than the default ‘UTF-8’.

store_schemabool, default False

If True, writes arrow schema to Parquet file footer’s key-value metadata section to faithfully round-trip duration types with arrow. This cannot be used with int96_timestamps enabled as int96 timestamps are deprecated in arrow. Also, all decimal32 and decimal64 columns will be converted to decimal128 as arrow only supports decimal128 and decimal256 types.

**kwargs

Additional parameters will be passed to execution engines other than cudf.