Expand description
Row-shape descriptor: the schema-of-bytes that explains how to interpret an EncodedRow.
A RowShape lists every field (name, type constraint, byte offset, byte size, alignment) so storage backends,
replication, and CDC can address fields without consulting the catalog. Submodules cover shape consolidation across
rows of the same logical schema, schema evolution rules for adding and removing fields, structural fingerprinting
used by plan caches and migration tooling, and conversion routines from typed schemas.
Invariant: the SHAPE_HEADER_SIZE constant and the packed-mode bit layout (mode bit, length mask, offset mask) are
part of the wire format. Reordering or resizing any of these regions silently breaks every row written under the
previous layout.