哥们 描述的不是很清楚
以下是我的理解 不知对不对select t1.字段名,...,t2.字段名,.....,t3.字段名,.......
from
t1,t2,t3
where A and t1.id = t2.id and t1.id = t3.id
以下是我的理解 不知对不对select t1.字段名,...,t2.字段名,.....,t3.字段名,.......
from
t1,t2,t3
where A and t1.id = t2.id and t1.id = t3.id
left join t2 on t1.id = t2.id
left join t3 on t1.id = t3.id
where A;
mathematician(数学家) 的好象应该是正确的.
近来都是客,接分吧