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Class: Aws::Firehose::Types::OrcSerDe

Inherits:
Struct
  • Object
show all
Defined in:
(unknown)

Overview

Note:

When passing OrcSerDe as input to an Aws::Client method, you can use a vanilla Hash:

{
  stripe_size_bytes: 1,
  block_size_bytes: 1,
  row_index_stride: 1,
  enable_padding: false,
  padding_tolerance: 1.0,
  compression: "NONE", # accepts NONE, ZLIB, SNAPPY
  bloom_filter_columns: ["NonEmptyStringWithoutWhitespace"],
  bloom_filter_false_positive_probability: 1.0,
  dictionary_key_threshold: 1.0,
  format_version: "V0_11", # accepts V0_11, V0_12
}

A serializer to use for converting data to the ORC format before storing it in Amazon S3. For more information, see Apache ORC.

Returned by:

Instance Attribute Summary collapse

Instance Attribute Details

#block_size_bytesInteger

The Hadoop Distributed File System (HDFS) block size. This is useful if you intend to copy the data from Amazon S3 to HDFS before querying. The default is 256 MiB and the minimum is 64 MiB. Kinesis Data Firehose uses this value for padding calculations.

Returns:

  • (Integer)

    The Hadoop Distributed File System (HDFS) block size.

#bloom_filter_columnsArray<String>

The column names for which you want Kinesis Data Firehose to create bloom filters. The default is null.

Returns:

  • (Array<String>)

    The column names for which you want Kinesis Data Firehose to create bloom filters.

#bloom_filter_false_positive_probabilityFloat

The Bloom filter false positive probability (FPP). The lower the FPP, the bigger the Bloom filter. The default value is 0.05, the minimum is 0, and the maximum is 1.

Returns:

  • (Float)

    The Bloom filter false positive probability (FPP).

#compressionString

The compression code to use over data blocks. The default is SNAPPY.

Possible values:

  • NONE
  • ZLIB
  • SNAPPY

Returns:

  • (String)

    The compression code to use over data blocks.

#dictionary_key_thresholdFloat

Represents the fraction of the total number of non-null rows. To turn off dictionary encoding, set this fraction to a number that is less than the number of distinct keys in a dictionary. To always use dictionary encoding, set this threshold to 1.

Returns:

  • (Float)

    Represents the fraction of the total number of non-null rows.

#enable_paddingBoolean

Set this to true to indicate that you want stripes to be padded to the HDFS block boundaries. This is useful if you intend to copy the data from Amazon S3 to HDFS before querying. The default is false.

Returns:

  • (Boolean)

    Set this to true to indicate that you want stripes to be padded to the HDFS block boundaries.

#format_versionString

The version of the file to write. The possible values are V0_11 and V0_12. The default is V0_12.

Possible values:

  • V0_11
  • V0_12

Returns:

  • (String)

    The version of the file to write.

#padding_toleranceFloat

A number between 0 and 1 that defines the tolerance for block padding as a decimal fraction of stripe size. The default value is 0.05, which means 5 percent of stripe size.

For the default values of 64 MiB ORC stripes and 256 MiB HDFS blocks, the default block padding tolerance of 5 percent reserves a maximum of 3.2 MiB for padding within the 256 MiB block. In such a case, if the available size within the block is more than 3.2 MiB, a new, smaller stripe is inserted to fit within that space. This ensures that no stripe crosses block boundaries and causes remote reads within a node-local task.

Kinesis Data Firehose ignores this parameter when OrcSerDe$EnablePadding is false.

Returns:

  • (Float)

    A number between 0 and 1 that defines the tolerance for block padding as a decimal fraction of stripe size.

#row_index_strideInteger

The number of rows between index entries. The default is 10,000 and the minimum is 1,000.

Returns:

  • (Integer)

    The number of rows between index entries.

#stripe_size_bytesInteger

The number of bytes in each stripe. The default is 64 MiB and the minimum is 8 MiB.

Returns:

  • (Integer)

    The number of bytes in each stripe.