表1
--------------------------------------------------------
| id | leiName | Nid | NName | Tid | Title |
| 2 | 类名1 | 4 | 手机 | 99 | ddddd |
| 3 | 类名2 | 5 | 手机1 | 98 | dererd |
| 6 | 类名3 | 3 | 手机 | 97 | dbbvd |
| 3 | 类名6 | 8 | 手机3 | 96 | 31231dd |
求,根据 Tid的从大到小排列,排3个结果,如 NName 相同的忽略
手机
手机1
手机//相同的忽略
手机3
mysql语句怎么写的。。
回复讨论(解决方案)
group by NName
select * from
(select * from 表1 order by Tid desc) tt
group by NNname;
select * from
(select * from 表1 order by Tid desc) tt
group by NNname;
tt 是表名1吗?
tt 是别名
tt 是别名
最后的结果集排序,乱了。没按 Tid 排序。
你的sql是如何写的。建议你贴出
create table....;
insert into table....; 语句
及期望结果,并给以简单的算法描述。
你的sql是如何写的。建议你贴出
create table....;
insert into table....; 语句
及期望结果,并给以简单的算法描述。
--------------------------------------------------------
| id | leiName | Nid | NName | Tid | Title |
| 2 | 类名1 | 4 | 手机 | 99 | ddddd |
| 3 | 类名2 | 5 | 手机1 | 98 | dererd |
| 6 | 类名3 | 3 | 手机 | 97 | dbbvd |
| 3 | 类名6 | 8 | 手机3 | 96 | 31231dd |
SQL 视图就这样的哦。然后就是根据 Tid来排序,
99 手机 ddddd
98 手机1 dererd
97 发现手机已经出现了,忽略,主要是怎么忽略这个。
96 手机2 31231dd
算了。我看使用数组来过滤好了。
如
Array
(
[id] => 39
[xClass] => 超级王
[Title] => 方式发送到
[NURL] =>
[CreateDate] => 2013-05-12 15:28:46
)
1
Array
(
[id] => 32
[DCName] => 玄
[CURL] =>
[Item1] => 风
[Nid] => 62325
[xClass] => 重天
[Title] => fsfsd
[CreateDate] => 2013-05-12 15:27:28
)
1
Array
(
[id] => 32
[DCName] => 玄
[CURL] =>
[Item1] => 风
[Nid] => 62324
[xClass] => 重天
[Title] => dddddddd43432
[CreateDate] => 2013-05-12 15:26:54
)
得到这样数组。
xclass = 重天。就排除,留1个。用那个函数。
运行#2的sql代码不行?
贴数组请贴出经 var_export() 后的数据。
$arr=你的数组;$t=array();foreach($arr as $v){ if(!isset($t[$v['xClass']])){ $t[$v['xClass']]=$v; }}print_r(array_values($t));
运行#2的sql代码不行?
贴数组请贴出经 var_export() 后的数据。
得到的结果列表很乱,不是按Tid 排序。同时 当出现1个手机后,第三排在出现没忽略。
while($rsrow=$result->fetch_assoc()){
echo '
'; <br> print_r($rsrow); <br> echo '';
}
得到的数组如下
Array
(
[id] => 3
[DCName] => 玄
[CURL] => 3
[Item1] => 唐
[Nid] => 62326
[xClass] => 超级王
[Title] => 方式发送到
[NURL] =>
[CreateDate] => 2013-05-12 15:28:46
)
Array
(
[id] => 3
[DCName] => 玄
[CURL] => 3
[Item1] => 唐
[Nid] => 62325
[xClass] => 重天
[Title] => fsfsd
[NURL] =>
[CreateDate] => 2013-05-12 15:27:28
)
Array
(
[id] => 3
[DCName] => 玄
[CURL] => 3
[Item1] => 唐少
[Nid] => 62324
[xClass] => 重天
[Title] => dddddddd43432
[NURL] =>
[CreateDate] => 2013-05-12 15:26:54
)
最终过滤 当 键 xClass的值 重天出现过1次后,以后则忽略。
这个函数时?
select * from 表1 group by NNname order by Tid desc
while($rsrow=$result->fetch_assoc()){
$arr[]=$rsrow;
}
然后用 #10 代码
孩纸,这样子的问题你需要去查资料,这样等这别人直接写出来的结果对你没什么帮助~~~~

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