数据库查询问题！ ( 积分: 10 )

L

leafsummer

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GUEST, unregistred user!

• 2005-11-08

• #1

ADOQuery1->Close();
ADOQuery1->SQL->Clear();
ADOQuery1->SQL->Add("select 起点横坐标,起点纵坐标,终点横坐标,终点纵坐标 from Path"
ADOQuery1->SQL->Add("where 路径编号=(select max(路径编号) from Path)"
ADOQuery1->Open();
我想要查询表中“路径编号”字段最大值的那行，按上面写的报错了，错在哪里了，应该怎么改啊？

 

L

leafsummer

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-11-08

• #2

ADOQuery1->Close();
ADOQuery1->SQL->Clear();
ADOQuery1->SQL->Add("select 起点横坐标,起点纵坐标,终点横坐标,终点纵坐标 from Path"
ADOQuery1->SQL->Add("where 路径编号=(select max(路径编号) from Path)"
ADOQuery1->Open();
我想要查询表中“路径编号”字段最大值的那行，按上面写的报错了，错在哪里了，应该怎么改啊？

 

F

free-spirit

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-11-08

• #3

where 路径编号=(select max(路径编号) from Path)
改為
where 路径编号 in (select max(路径编号) from Path)

 

L

leafsummer

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• 2005-11-08

• #4

还是出错，报错为：参数 路径编号没有默认值

 

W

wwr74

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• 2005-11-08

• #5

报的错误是什么？是不是引号错了？

 

L

lijun_snut

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• 2005-11-08

• #6

ADOQuery1->Close();
ADOQuery1->SQL->Clear();
ADOQuery1->SQL->Add("select 起点横坐标,起点纵坐标,终点横坐标,终点纵坐标 from Path"
ADOQuery1->SQL->Add("where 路径编号=(select max(路径编号) as xx from Path)"
ADOQuery1->Open();

 

Y

yitang

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• 2005-11-11

• #7

ADOQuery1->Close();
ADOQuery1->SQL->Clear();
ADOQuery1->SQL->Add('select 起点横坐标,起点纵坐标,终点横坐标,终点纵坐标 from Path');
ADOQuery1->SQL->Add('where 路径编号=(select max(路径编号) from Path)');
ADOQuery1->Open();

 

L

leafsummer

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-11-14

• #8

多人接受答案了。