SELECT *
FROM PARENTINF
LEFT JOIN GRADE ON PARENTINF.GRADE_CODE = GRADE.GRADE_CODE
INNER JOIN class ON PARENTINF.GRADE_CODE = CLASS.CLASS_CODE
FROM PARENTINF
LEFT JOIN GRADE ON PARENTINF.GRADE_CODE = GRADE.GRADE_CODE
INNER JOIN class ON PARENTINF.GRADE_CODE = CLASS.CLASS_CODE
解决方案 »
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