Expand description
Constants for Lance encoding metadata keys
These constants define the metadata keys used in Arrow field metadata to configure various encoding behaviors in Lance.
Constants§
- BSS_
META_ KEY - Metadata key for byte stream split encoding configuration
- COMPRESSION_
LEVEL_ META_ KEY - Metadata key for specifying compression level (applies to schemes that support levels)
- COMPRESSION_
META_ KEY - Metadata key for specifying compression scheme (e.g., “lz4”, “zstd”, “none”)
- DEFAULT_
BSS_ MODE - Default BSS mode
- DICT_
DIVISOR_ META_ KEY - Metadata key for specifying dictionary encoding threshold divisor Set to a large value to discourage dictionary encoding Set to a small value to encourage dictionary encoding
- DICT_
SIZE_ RATIO_ META_ KEY - Metadata key for dictionary encoding size ratio threshold (0.0-1.0] If estimated_dict_size/raw_size < ratio, use dictionary encoding. Example: 0.8 means use dict if encoded size < 80% of raw size Default: 0.8
- PACKED_
STRUCT_ LEGACY_ META_ KEY - Legacy metadata key for packed struct encoding (deprecated)
- PACKED_
STRUCT_ META_ KEY - Metadata key for packed struct encoding
- RLE_
THRESHOLD_ META_ KEY - Metadata key for specifying RLE (Run-Length Encoding) threshold
- STRUCTURAL_
ENCODING_ FULLZIP - Value for fullzip structural encoding
- STRUCTURAL_
ENCODING_ META_ KEY - Metadata key for specifying structural encoding type
- STRUCTURAL_
ENCODING_ MINIBLOCK - Value for miniblock structural encoding