Order of chained JOINs

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Accepted Answer

The SQL standard guarantees that JOIN is logically commutative and associative for inner joins - the optimizer is free to reorder them for efficiency. What determines correctness is the ON condition, not the physical order of JOIN clauses in your SQL. That said, LEFT JOINs are order-sensitive in terms of which rows are preserved, so be deliberate when mixing inner and outer joins in the same chain.