access，在一条语句中进行多连接
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通过对《课程》表实施自连接操作，可生成如下所示的交叉表格
select *
from
(((
(SELECT DISTINCT mname FROM 课程) C0
LEFT JOIN
(SELECT mname as SQL_name FROM 课程 WHERE course = 'SQL入门' ) as C1
ON C0.mname = C1.sql_name )
LEFT JOIN
(SELECT mname as UNIX_name FROM 课程 WHERE course = 'UNIX基础' ) as C3
ON C0.mname = C3.UNIX_name )
LEFT JOIN
(SELECT mna全部评论 (0)
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