fix(datafusion): map column-less MERGE INSERT VALUES by position - #984
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jackylee-ch wants to merge 1 commit into
Open
jackylee-ch wants to merge 1 commit into
jackylee-ch wants to merge 1 commit into
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`WHEN NOT MATCHED THEN INSERT VALUES (s.a, s.b, ...)` without an explicit column list built an empty column->expression map, so `insert_select_clause` emitted `NULL` for every target column and dropped the source values. The merge then inserted all-NULL rows (or failed on a non-null column) instead of the source data — silent corruption for a column-less positional INSERT, which is valid standard SQL (the MERGE INSERT column list is optional) and accepted by DataFusion's parser. Map the VALUES to the table's columns by position when no column list is given, and reject a value/column count mismatch. Explicit-column and `INSERT *` clauses are unchanged. Added an end-to-end MERGE test using a column-less INSERT; it inserts all-NULL rows before the fix.
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WHEN NOT MATCHED THEN INSERT VALUES (s.a, s.b, ...)without an explicit column list built an empty column->expression map, soinsert_select_clauseemittedNULLfor every target column and dropped the source values. The merge then inserted all-NULL rows (or failed on a non-null column) instead of the source data — silent corruption for a column-less positional INSERT. This form is valid standard SQL (the MERGE INSERT column list is optional) and DataFusion's parser accepts it; Spark's own MERGE grammar, by contrast, requires an explicit column list orINSERT *. The existing MERGE INSERT tests all pass an explicit column list, so this went uncovered.Map the VALUES to the table's columns by position when no column list is given, and reject a value/column count mismatch. Explicit-column and
INSERT *clauses are unchanged.Added an end-to-end MERGE test using a column-less INSERT; it inserts all-NULL rows before the fix.