多联接左联接中哪个表是左表?

问题描述 投票:0回答:0
SELECT *
FROM t1
JOIN t2 ON t2.id = t1.t2_id
LEFT JOIN t3 ON t3.id = t2.t3_id
LEFT JOIN t4 ON t4.id = t1.t4_id

左加入t4时哪个是左表?是先前的结果集 - 先前连接的组合,还是之前的表,即 t3,还是因为 ON 子句而成为 t1?

sql database tsql join left-join
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