select l.linkid,n.nodename,n.nodename from links l,nodes n where l.enternodeid=n.nodeid and l.exitnodeid=n.nodeid and l.linkid=1 这个SQL语句查询的时候不报错,也不现实数据 还有就是l.enternodeid=n.nodeid and l.exitnodeid=n.nodeid 是这样的 两个字段要根据一个字段查询不同的数据 例如:表1 enternodeid exi
[Quote=引用 8 楼 merrill 的回复:]
select l.linkid, n.nodename, m.nodename
from links l, nodes n, nodes m
where l.enternodeid = n.nodeid
and l.exitnodeid = m.nodeid
and l.linkid = 1
[/Quote]
试试吧……
SQL code
select linkid,
(select max(nodename)from nodes n where l.enternodeid = n.nodeid),--起始路段名称
(select max(nodename)from nodes n where l.exitnodeid = n.nodeid)--终止路段名称
from links l
[/Quote]
[Quote=引用 7 楼 merrill 的回复:]
select l.linkid, n.nodename, m.nodename
from links l, nodes n, nodes m
where l.enternodeid = n.nodeid
and l.exitnodeid = m.nodeid
and l.linkid = 1
[/Quote]
select linkid,
(select max(nodename)from nodes n where l.enternodeid = n.nodeid),--起始路段名称
(select max(nodename)from nodes n where l.exitnodeid = n.nodeid)--终止路段名称
from links l