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new 57ec535d0e Revert "[SPEC] Add implementation note about schema
evolution (#13936)" (#14002)
57ec535d0e is described below
commit 57ec535d0ed749d93c93f8dba085ee70ad6eee84
Author: emkornfield <[email protected]>
AuthorDate: Fri Sep 5 13:00:07 2025 -0700
Revert "[SPEC] Add implementation note about schema evolution (#13936)"
(#14002)
This reverts commit c64c89fbb5390c7c796e022b939118539c7195e1.
---
format/spec.md | 10 ----------
1 file changed, 10 deletions(-)
diff --git a/format/spec.md b/format/spec.md
index 1f5b55eed8..029b4f3821 100644
--- a/format/spec.md
+++ b/format/spec.md
@@ -1861,16 +1861,6 @@ Java writes `-1` for "no current snapshot" with V1 and
V2 tables and considers t
Some implementations require that GZIP compressed files have the suffix
`.gz.metadata.json` to be read correctly. The Java reference implementation can
additionally read GZIP compressed files with the suffix `metadata.json.gz`.
-### Schema evolution and writing with old schemas
-
-Writers must write out all fields with the types specified from a schema
present in table metadata. Writers should use the latest schema for writing.
Not writing out all columns or not using the latest schema can change the
semantics of the data written. The following are possible inconsistencies that
can be introduced:
-
-* For all null columns, not writing out the column would cause
`initial-default` value would be applied on reading instead of `null`.
-* If `write-default` has been changed then using an out-of-date schema would
result in the incorrect value being populated.
-* If a `write` is the result of a partial row update (e.g. `update table set
col_y = 'xyz'`) an out-of-date schema would silently drop values.
-
-Column projection rules are designed so that the table will remain readable
even if writers use an outdated schema.
-
## Appendix G: Geospatial Notes
The Geometry and Geography class hierarchy and its Well-known text (WKT) and
Well-known binary (WKB) serializations (ISO supporting XY, XYZ, XYM, XYZM) are
defined by [OpenGIS Implementation Specification for Geographic information –
Simple feature access – Part 1: Common
architecture](https://portal.ogc.org/files/?artifact_id=25355), from [OGC (Open
Geospatial Consortium)](https://www.ogc.org/standard/sfa/).
