fix: missing column comments after ALTER VIEW AS#1444
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Signed-off-by: Can Bekleyici <can.bekleyici@deepl.com>
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Resolve conflict in tests/unit/macros/relations/test_view_macros.py by keeping both additions: this branch's alter_column_comment mock + the reapplies_column_comments test, and main's (databricks#1526) apply_column_tags mock + the column_tags test. They are independent. Relocate the databricks#1357 CHANGELOG entry out of the now-released 1.11.8 section into the current 1.12.2 (TBD) Fixes section (main has since released 1.11.8/1.12.0/1.12.1).
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Changes look good, thanks for the PR !!
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Resolves #1357
Split out from #1358 per maintainer request to land independently of the #1356 behavior change.
Description
When
view_update_via_alteris enabled and the alter path issuesALTER VIEW <view> AS <query>,Databricks silently drops every persisted column comment. The existing
if column_commentsblockin
databricks__alter_viewdoesn't catch this because the column-comment diff is computed againstthe pre-alter state — when model and existing comments match, the diff is empty, so nothing
reapplies them after
ALTER VIEW ASwipes them.Fix: inside the
querybranch ofdatabricks__alter_view, reapply persisted column commentsafter
alter_query, gated onconfig.persist_column_docs()andmodel.columns. The patternmirrors
databricks__persist_docs(dbt/include/databricks/macros/adapters/persist_docs.sql).The existing
if column_commentsblock is kept — it still handles the disjoint case where only acolumn description changed in
schema.yml(no query change, so the new reapply path doesn't run).This fix becomes load-bearing once #1356 lands and
ALTER VIEW ASruns on every invocation, butthe bug exists today on any query change and is worth fixing standalone.
Checklist
CHANGELOG.mdand added information about my change to the"dbt-databricks next" section.