SELECT[DISTINCT]
FROM
WHERE
GROUP BY
HAVING
UNION
ORDER BY
FROM
WHERE
GROUP BY
HAVING
SELECT
DISTINCT
UNION
ORDER BY
EQUI JOIN
SEMI JOIN
ANTI JOIN
CROSS JOIN
DIVISION
EQUI JOIN
INNER JOIN(或者是 JOIN )
OUTER JOIN(包括: LEFT 、 RIGHT、 FULL OUTER JOIN)
IN比 EXISTS 的可读性更好
EXISTS 比IN 的表达性更好(更适合复杂的语句)
CDA数据分析师(cdacdacda)
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