请教一条SQL语句

Question

我想用一条语句找出数据表中不用的4条记录,如何写呢?
select c.CompanyID,c.CompanyName,m.ModelName,m.ModelUrl,m.MiniatureUrl from companyinfo c,modelinfo m where c.CompanyID=m.OwerID and c.VRFactory is not null order by c.point desc,c.propose desc,c.ModifyTime desc limit 0,4
如何改这条语句呢.谢谢啦

Answer 1

楼主最好用 INNER JOIN 标准写法一般连接查询，肯定有一个字段来做关系，你就查没有被关系上的数据不就行了例如
 SELECT * FROM 表A INNER JOIN 表B ON 表A.**ID = 表B.**ID WHERE 表B.**ID IS NULL

Answer 2

表的字段太多了
+--------------+------------------------------+------+-----+--------------------
+----------------+
| Field        | Type                         | Null | Key | Default
| Extra          |
+--------------+------------------------------+------+-----+--------------------
+----------------+
| CompanyID    | int(10) unsigned             | NO   | PRI | NULL
| auto_increment |
| UserName     | varchar(50)                  | YES  |     | NULL
|                |
| UserPWD      | varchar(50)                  | YES  |     | NULL
|                |
| CompanyName  | varchar(255)                 | YES  |     | NULL
|                |
| Province     | varchar(45)                  | YES  |     | NULL
|                |
| City         | varchar(45)                  | YES  |     | NULL
|                |
| NeedInfo     | varchar(1255)                | YES  |     | NULL
|                |
| Property     | tinyint(1) unsigned          | YES  |     | NULL
|                |
| Intro        | varchar(4000)                | YES  |     | NULL
|                |
| EMail        | varchar(45)                  | NO   |     |
|                |
| Tel          | varchar(45)                  | NO   |     |
|                |
| VRFactory    | int(10) unsigned             | YES  |     | NULL
|                |
| History      | varchar(45)                  | YES  |     | NULL
|                |
| IndustryType | int(10) unsigned             | YES  |     | 3
|                |
| Type         | tinyint(1) unsigned zerofill | NO   |     |
|                |
| ModifyTime   | datetime                     | NO   |     |
|                |
| State        | tinyint(1) unsigned          | NO   |     | 0
|                |
| LogoUrl      | varchar(45)                  | YES  |     | ./logo/default.gif
|                |
| RegTime      | datetime                     | NO   |     |
|                |
| incorporator | varchar(45)                  | YES  |     | NULL
|                |
| licenseNum   | varchar(45)                  | YES  |     | NULL
|                |
| taxpayerNum  | varchar(45)                  | YES  |     | NULL
|                |
| employeeNum  | varchar(45)                  | YES  |     | NULL
|                |
| regCapital   | int(10) unsigned             | YES  |     | NULL
|                |
| totalSells   | int(10) unsigned             | YES  |     | NULL
|                |
| linkman      | varchar(45)                  | YES  |     | NULL
|                |
| address      | varchar(255)                 | YES  |     | NULL
|                |
| postalCode   | varchar(20)                  | YES  |     | NULL
|                |
| website      | varchar(45)                  | YES  |     | NULL
|                |
| phoneNum     | varchar(20)                  | YES  |     | NULL
|                |
| fax          | varchar(20)                  | YES  |     | NULL
|                |
| times        | int(10) unsigned             | NO   |     | 0
|                |
| recommTimes  | int(10) unsigned             | NO   |     | 0
|                |
+--------------+------------------------------+------+-----+--------------------

Answer 3

这是其中的一个表
还有一个是
---------+
| Field           | Type                      | Null | Key | Default    | Extra
         |
+-----------------+---------------------------+------+-----+------------+-------
---------+
| ModelID         | int(10) unsigned          | NO   | PRI | NULL       | auto_i
ncrement |
| OwerID          | int(10) unsigned          | NO   |     | 0          |
         |
| ModelName       | varchar(100)              | NO   |     |            |
         |
| ModelUrl        | varchar(255)              | YES  |     | NULL       |
         |
| MiniatureUrl    | varchar(255)              | YES  |     | NULL       |
         |
| Re          | varchar(1255)             | YES  |     | NULL       |
         |
| AccessoriesUrl  | varchar(255)              | YES  |     | NULL       |
         |
| ModelSize       | int(10) unsigned zerofill | YES  |     | 0000000000 |
         |
| Type            | int(10) unsigned          | YES  | MUL | 0          |
         |
| ModelPrice      | float                     | YES  |     | 0          |
         |
| ModelRentPrice  | float unsigned            | YES  |     | 0          |
         |
| ProductPrice    | float unsigned            | YES  |     | 0          |
         |
| IsPublic        | tinyint(1) unsigned       | NO   |     | 0          |
         |
| IsImage         | tinyint(1) unsigned       | NO   |     | 0          |
         |
| FolderID        | int(10) unsigned zerofill | NO   |     | 0000000000 |
         |
| MiniatureSize   | int(10) unsigned          | YES  |     | NULL       |
         |
| AccessoriesSize | int(10) unsigned          | YES  |     | NULL       |
         |
| ModifyTime      | datetime                  | NO   |     |            |
         |
| State           | tinyint(1) unsigned       | YES  |     | 0          |
         |
| recommTimes     | int(10) unsigned          | NO   |     | 0          |
         |
+-----------------+---------------------------+------+-----+------------+-------

Answer 4

如果是随便4条的话我建议加上 group by .这样出来的话一定是不会一样的.