Apache group file format

In its most simplistic form, we cater for a user that wants to read the whole Parquet at once with the FileReader::ReadTable method. More advanced users that also want to implement parallelism on top of each single Parquet files should do this on the RowGroup level.

FileReaders must outlive their RecordBatchReaders. Return a reader for the RowGroup, this object must not outlive the FileReader. Build FileReader instance. Advanced settings are supported through the FileReaderBuilder class. The values given must be of the correct type i.

The user must explicitly advance to the next row using the EndRow function or EndRow input manipulator. However, if the value is not present then a ParquetException will be raised. ParquetException — if all columns in the row were not read or skipped. If the number of columns exceeds the columns remaining on the current row then skipping is terminated - it does not continue skipping columns on the next row.

Skipping of rows is not allowed if reading of data for the current row is not finished. Skipping of rows will be terminated if the end of file is reached. This either apply if dictionary encoding is disabled or if we fallback as the dictionary grew too large. In case a column does not have an explicitly specified compression level, the default one would be used.

The provided compression level is compressor specific. The user would have to familiarize oneself with the available levels for the selected compressor. If the compressor does not allow for selecting different compression levels, calling this function would not have any effect.

Parquet and Arrow do not validate the passed compression level. Older versions of arrow wrote out field names for nested lists based on the name of the field. V2 is currently the latest V1 is considered deprecated but left in place in case there are bugs detected in V2. Iterative FileWriter class. The user must explicitly indicate the end of the row using the EndRow function or EndRow output manipulator. A maximum row group size can be configured, the default size is MB.

Alternatively the row group size can be set to zero and the user can create new row groups by calling the EndRowGroup function or using the EndRowGroup output manipulator.

However if the optional parameter does not have a value i. ParquetException — if there is an attempt to skip any required column. ParquetException — if all columns in the row were not written or skipped.

DataType pyarrow. DictionaryType pyarrow. ListType pyarrow. MapType pyarrow. StructType pyarrow. UnionType pyarrow. TimestampType pyarrow. Time32Type pyarrow. Time64Type pyarrow. FixedSizeBinaryType pyarrow. DecimalType pyarrow. Field pyarrow. Schema pyarrow.

ExtensionType pyarrow. PyExtensionType pyarrow. Array pyarrow. BooleanArray pyarrow. FloatingPointArray pyarrow. IntegerArray pyarrow. Int8Array pyarrow. Int16Array pyarrow. Int32Array pyarrow. Int64Array pyarrow. NullArray pyarrow. NumericArray pyarrow. UInt8Array pyarrow.

UInt16Array pyarrow. UInt32Array pyarrow. UInt64Array pyarrow. BinaryArray pyarrow. StringArray pyarrow. FixedSizeBinaryArray pyarrow.

LargeBinaryArray pyarrow. LargeStringArray pyarrow. Time32Array pyarrow. Time64Array pyarrow. Date32Array pyarrow. Date64Array pyarrow. TimestampArray pyarrow. DurationArray pyarrow. MonthDayNanoIntervalArray pyarrow. DecimalArray pyarrow. DictionaryArray pyarrow. ListArray pyarrow. FixedSizeListArray pyarrow. LargeListArray pyarrow. StructArray pyarrow. UnionArray pyarrow. ExtensionArray pyarrow. NA pyarrow. Scalar pyarrow. Int8Scalar pyarrow.

Int16Scalar pyarrow. Int32Scalar pyarrow. Int64Scalar pyarrow. UInt8Scalar pyarrow. UInt16Scalar pyarrow. UInt32Scalar pyarrow. UInt64Scalar pyarrow. FloatScalar pyarrow. DoubleScalar pyarrow. BinaryScalar pyarrow. StringScalar pyarrow. FixedSizeBinaryScalar pyarrow. LargeBinaryScalar pyarrow. LargeStringScalar pyarrow. Time32Scalar pyarrow. Time64Scalar pyarrow. Date32Scalar pyarrow. Date64Scalar pyarrow. TimestampScalar pyarrow.

DurationScalar pyarrow. MonthDayNanoIntervalScalar pyarrow. DecimalScalar pyarrow. DictionaryScalar pyarrow. ListScalar pyarrow. LargeListScalar pyarrow. StructScalar pyarrow. UnionScalar Buffers and Memory pyarrow. Buffer pyarrow. ResizableBuffer pyarrow. Codec pyarrow. MemoryPool pyarrow. NativeFile pyarrow. OSFile pyarrow. PythonFile pyarrow.

BufferReader pyarrow. BufferOutputStream pyarrow. FixedSizeBufferWriter pyarrow. MemoryMappedFile pyarrow. CompressedInputStream pyarrow. CompressedOutputStream pyarrow. LocalFileSystem Tables and Tensors pyarrow. ChunkedArray pyarrow. RecordBatch pyarrow. Table pyarrow. Tensor Serialization and IPC pyarrow. IpcWriteOptions pyarrow. Message pyarrow. MessageReader pyarrow. RecordBatchFileReader pyarrow. RecordBatchFileWriter pyarrow. RecordBatchStreamReader pyarrow.

RecordBatchStreamWriter pyarrow. SerializedPyObject pyarrow. SerializationContext Arrow Flight pyarrow. Action pyarrow. ActionType pyarrow. DescriptorType pyarrow. FlightDescriptor pyarrow. FlightEndpoint pyarrow. FlightInfo pyarrow. Location pyarrow. Ticket pyarrow. Result pyarrow. FlightCallOptions pyarrow. FlightClient pyarrow. ClientMiddlewareFactory pyarrow.

ClientMiddleware pyarrow. FlightServerBase pyarrow. GeneratorStream pyarrow. RecordBatchStream pyarrow. ServerMiddlewareFactory pyarrow. ServerMiddleware pyarrow. ClientAuthHandler pyarrow. ServerAuthHandler pyarrow. FlightMethod pyarrow. CallInfo Tabular File Formats pyarrow. ConvertOptions pyarrow. CSVStreamingReader pyarrow. CSVWriter pyarrow. ISO pyarrow. By default, it is set to seconds, which is appropriate for most situations.

KeepAlive It sets whether the server allows more than one request per connection and can be used to prevent a client from using too much of the servers resources. By default, KeepAlive is set to off that means server does not allow continuous connections. It is set to by default, which should be suitable for most situations. KeepAliveTimeout This directive sets the number of seconds your server will wait for next request, after a request has been served before it closes the connection.

By default, it is set to 15 seconds. StartServers This directive sets how many server processes are created upon startup. The Web server is set to start 8 server processes at startup. MaxClients Maxclients sets a limit on the total number of server processes that can run simultaneously at one time.

The main purpose of this directive is to keep a runaway web server from crashing the operating system. By default, it is set to The order of modules is important. User It sets the userid used by the server to answer the requests. User is not allowed to execute any code that is not intended to be in response to HTTP requests. By default, User is set to Apache. Group It is similar to the User. The Group sets the groupid under which the server will answer requests.