[python] support blob type and blob write and read

[jerry-024]

Purpose

Support blob type and blob write and read

Tests

• blob_test.BlobTest
• blob_test.BlobEndToEndTest

API and Format

Documentation

[Copilot]

Pull Request Overview

This PR adds comprehensive support for BLOB (Binary Large Object) data type in the Python Paimon library, including data structures, I/O operations, and format handling.

• Implements BLOB data type with BlobData and BlobRef classes for in-memory and reference-based storage
• Adds blob-specific file format writer and reader with compression and indexing
• Integrates BLOB support into existing serialization, type conversion, and file I/O systems

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
blob.py	Core BLOB data structures and interface definitions
blob_format_writer.py	Writer for Paimon's blob file format with compression
format_blob_reader.py	Reader for blob files with decompression and indexing
generic_row.py	Serialization support for BLOB fields
data_types.py	Type system integration for BLOB
file_io.py	File I/O operations for blob format
delta_varint_compressor.py	Compression utility for blob index data
core_options.py	Configuration constant for blob format
split_read.py	Integration of blob reader into split reading
blob_test.py	Comprehensive test suite for all blob functionality

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[Copilot]

Pull Request Overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 3 comments.

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[Copilot]

The magic number 12 represents the combined size of length (8 bytes) and CRC (4 bytes) fields. Consider defining this as a named constant like METADATA_SIZE = 12 to improve code clarity and maintainability.

[Copilot]

Pull Request Overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated 5 comments.

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[leaves12138]

+1