Module row_serialization 

Row serialization for disk spilling

This module provides compact binary serialization for rows and sort keys, optimized for external sort and aggregate operations.

Format

Each row is serialized as:

[num_values: u16] [value1] [value2] ... [valueN]

Each value is serialized as:

[type_tag: u8] [data...]

Design Decisions

• No length prefix for entire row: We write rows sequentially and read them back in chunks, so we don’t need random access within a run.
• Compact type tags: Single byte discriminant for common types
• Little-endian: Matches most modern hardware for zero-copy potential

Functions

deserialize_row

Deserialize a row from the reader

deserialize_row_with_keys

Deserialize a row with its sort keys

deserialize_value

Deserialize a single SqlValue from the reader

estimate_serialized_size

Estimate the serialized size of a row in bytes

serialize_row

Serialize a row to the writer

serialize_row_with_keys

Serialize a row with its sort keys

serialize_value

Serialize a single SqlValue to the writer