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Field	Size	Comments
Schema version	2 bytes.	short number. The possible values are: positive - regular row: key and value chunks are present; 0 - no value. If the flag is set, the value chunk is omitted, e.g. the row represents a tombstone or key-row to lookup by the key; negative - invalid schema version.
Key columns hash	4 bytes
Key chunk:
Key chunk size	4 bytes
Flags	1 byte
Variable-length columns offsets table size	2 or 0 bytes	Vartable is skipped (zero size) when the chunk contains one varlen column or doesn't contain varlen column.
Variable-length columns offsets table	Variable (number of non-null varlen columns * <format_size>)	<format_size> - depends on the Flags field. See the table below
Fix-sized columns values	Variable
Variable-length columns values	Variable
Value chunk:
Value chunk size	4 bytes
Flags	1 byte
Null-map	(number of columns / 8 ) or 0 bytes	Zero size if and only if schema has no nullable columns
Variable-length columns offsets table size	2 or 0 bytes	Vartable is skipped (zero size) when the chunk contains one varlen column or doesn't contain varlen column.
Variable-length columns offsets table	Variable (number of non-null varlen columns * <format_size>)	<format_size> - depends on the Flags field. See the table below
Fix-sized columns values	Variable
Variable-length columns values	Variable

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