fix(update): keep nested-field index correct when updating a struct column#7412
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jackye1995 merged 1 commit intoJun 23, 2026
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…olumn The update API rejects nested column references, so a nested field can only be changed by setting its whole top-level struct column. commit_impl built `fields_for_preserving_frag_bitmap` from the struct's own (parent) field id, so an index on a nested child field was absent from the set. The RewriteRows index maintenance then wrongly extended that child-field index over the rewritten fragment, leaving the updated rows unscanned and silently dropped from queries on the index. Collect the full field subtree of each updated column so indices on nested child fields are recognized as modified. Flat columns are unaffected.
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westonpace
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Jun 23, 2026
| dataset: Arc<Dataset>, | ||
| update_data: UpdateData, | ||
| ) -> Result<UpdateResult> { | ||
| // Updated columns are top-level (nested references are rejected by `set`), but a |
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I'm surprised that updated columns have to be top-level? I would think we could do an update on a nested column.
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The update API rejects nested column references (
seterrors on a.in the column name), so a nested field can only be changed by setting its whole top-level struct column (e.g.SET s = named_struct('x', …)).commit_implbuiltfields_for_preserving_frag_bitmapfrom the struct column's own (parent) field id viafield_id(column_name), so an index on a nested child field (a different leaf id) was absent from the set.register_pure_rewrite_rows_update_frags_in_indicesthen wrongly extended that child-field index over the rewritten fragment, which was therefore treated as indexed and never re-scanned — so the updated rows were silently dropped from queries on the index (false negatives).The fix collects the full field subtree of each updated column, so a struct-column update marks all descendant field ids as modified. Flat columns are unaffected (no children).
This is the SQL
UPDATEcounterpart of the merge_insert fix in #7410. Adds a regression test (test_update_struct_column_keeps_nested_index): a BTree index ons.x, an update of the struct columns, and an assertion that the index's effective fragment bitmap is not extended over the rewritten fragment so the updated value is still found.