Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Inner**: Only matching rows; A ⋂ B. **Left**: All A; B columns NULL where no match. **Right**: All B; A columns NULL where no match. **Schema**: Joins produce result set, not stored schema. Column set = A.columns + B.columns; aliases for disambiguation....
Inner: Only matching rows; A ⋂ B. Left: All A; B columns NULL where no match. Right: All B; A columns NULL where no match. Schema: Joins produce result set, not stored schema. Column set = A.columns + B.columns; aliases for disambiguation. Full outer: All from both.
Red Flag: Assuming join creates a new table. Pro-Move: 'We created a view with explicit column list to avoid * and control output schema for downstream consumers.'
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