Flow PHP

ColumnChunk

Properties

$_TSPEC : mixed
$column_index_length : null|int: Size of ColumnChunk's ColumnIndex, in bytes *
$column_index_offset : null|int: File offset of ColumnChunk's ColumnIndex *
$crypto_metadata : null|ColumnCryptoMetaData: Crypto metadata of encrypted columns *
$encrypted_column_metadata : null|string: Encrypted column metadata for this chunk *
$file_offset : int: DEPRECATED: Byte offset in file_path to the ColumnMetaData
$file_path : null|string: File where column data is stored. If not set, assumed to be same file as metadata. This path is relative to the current file.
$isValidate : mixed
$meta_data : null|ColumnMetaData: Column metadata for this chunk. Some writers may also replicate this at the location pointed to by file_path/file_offset.
$offset_index_length : null|int: Size of ColumnChunk's OffsetIndex, in bytes *
$offset_index_offset : null|int: File offset of ColumnChunk's OffsetIndex *

Methods

__construct() : mixed
getName() : mixed
read() : mixed
write() : mixed

$_TSPEC


        public
        static    mixed
    $_TSPEC
     = array(1 => array('var' => 'file_path', 'isRequired' => false, 'type' => \Thrift\Type\TType::STRING), 2 => array('var' => 'file_offset', 'isRequired' => true, 'type' => \Thrift\Type\TType::I64), 3 => array('var' => 'meta_data', 'isRequired' => false, 'type' => \Thrift\Type\TType::STRUCT, 'class' => '\Flow\Parquet\ThriftModel\ColumnMetaData'), 4 => array('var' => 'offset_index_offset', 'isRequired' => false, 'type' => \Thrift\Type\TType::I64), 5 => array('var' => 'offset_index_length', 'isRequired' => false, 'type' => \Thrift\Type\TType::I32), 6 => array('var' => 'column_index_offset', 'isRequired' => false, 'type' => \Thrift\Type\TType::I64), 7 => array('var' => 'column_index_length', 'isRequired' => false, 'type' => \Thrift\Type\TType::I32), 8 => array('var' => 'crypto_metadata', 'isRequired' => false, 'type' => \Thrift\Type\TType::STRUCT, 'class' => '\Flow\Parquet\ThriftModel\ColumnCryptoMetaData'), 9 => array('var' => 'encrypted_column_metadata', 'isRequired' => false, 'type' => \Thrift\Type\TType::STRING))

$column_index_length

Size of ColumnChunk's ColumnIndex, in bytes *


        public
            null|int
    $column_index_length
     = null

$column_index_offset

File offset of ColumnChunk's ColumnIndex *


        public
            null|int
    $column_index_offset
     = null

$crypto_metadata

Crypto metadata of encrypted columns *


        public
            null|ColumnCryptoMetaData
    $crypto_metadata
     = null

$encrypted_column_metadata

Encrypted column metadata for this chunk *


        public
            null|string
    $encrypted_column_metadata
     = null

$file_offset

DEPRECATED: Byte offset in file_path to the ColumnMetaData


        public
            int
    $file_offset
     = 0

Past use of this field has been inconsistent, with some implementations using it to point to the ColumnMetaData and some using it to point to the first page in the column chunk. In many cases, the ColumnMetaData at this location is wrong. This field is now deprecated and should not be used. Writers should set this field to 0 if no ColumnMetaData has been written outside the footer.

$file_path

File where column data is stored. If not set, assumed to be same file as metadata. This path is relative to the current file.


        public
            null|string
    $file_path
     = null

As of December 2025, the only known use-case for this field is writing summary parquet files (i.e. "_metadata" files). These files consolidate footers from multiple parquet files to allow for efficient reading of footers to avoid file listing costs and prune out files that do not need to be read based on statistics.

These files do not appear to have ever been formally specified in the specification. and are potentially problematic from a correctness perspective [1].

[1] https://lists.apache.org/thread/ootf2kmyg3p01b1bvplpvp4ftd1bt72d

There is no other known usage of this field. Specifically, there are no known reference implementations that will read externally stored column data if this field is populated within a standard parquet file. Making use of the field for this purpose is not considered part of the Parquet specification.

$isValidate


        public
        static    mixed
    $isValidate
     = false

$meta_data

Column metadata for this chunk. Some writers may also replicate this at the location pointed to by file_path/file_offset.


        public
            null|ColumnMetaData
    $meta_data
     = null

Note: while marked as optional, this field is in fact required by most major Parquet implementations. As such, writers MUST populate this field.

$offset_index_length

Size of ColumnChunk's OffsetIndex, in bytes *


        public
            null|int
    $offset_index_length
     = null

$offset_index_offset

File offset of ColumnChunk's OffsetIndex *


        public
            null|int
    $offset_index_offset
     = null

__construct()


    public
                    __construct([mixed $vals = null ]) : mixed

Parameters

$vals : mixed = null

getName()


    public
                    getName() : mixed

read()


    public
                    read(mixed $input) : mixed

Parameters

$input : mixed

write()


    public
                    write(mixed $output) : mixed

Parameters

$output : mixed