Question

请帮我写下面的更新查询。我正在使用SQL Server 2014。

要求：根据项目ID更新表C，获取相应的答案权利＆＃39;相应项目ID和最新记录的值。表A＆＃39;最新＆＃39; =＆＃39;是＆＃39;意味着它是最新的记录。基于＆＃39; Link_Id＆＃39;表A和B是链接的。表A和C基于＆＃39; Project_Id＆＃39;

表A：

＆＃13;

<table>
<tr>
<th>
Request Type | 
</th>
<th>Project ID  | </th>
<th>Latest |</th>
<th>	Link_ID</th>
</tr>
<tr>
-----------------------------------------------
</tr>
<tr>
<td>

a	
</td>
<td>1000</td>	<td>No</td>	<td>1</td>
</tr>
<tr>
<td>b</td>	<td>1005</td>	<td>Yes </td>      	<td>2</td>
<tr>
<td>123</td>	<td>1000</td><td>Yes   </td>    	<td>4</td></tr>
<tr>
<td>c	</td><td>1005</td>	<td>No</td>	<td>3</td></tr>
</table>

＆＃13;

表B

＆＃13;

<table>
<tr>
<th>
Question</th>	<th>Description</th>	<th>Answer_weightage</th>	<th>Link_ID
</th>

</tr>

<tr><td>
6	</td><td>Question6	</td><td>0</td>	<td>2</td>
</tr>
<tr>
<td>2</td>	<td>Question2</td>	<td>5</td>	<td>4</td></tr>
<tr>
<td>3</td>	<td>Question3	</td><td>5</td>	<td>4</td></tr>
<tr>
<td>4</td>	<td>Question4</td><td>	5</td>	<td>4</td></tr>
<tr>
<td>5	</td><td>Question5	</td><td>2</td>	<td>4</td></tr>
<tr>
<td>6</td>	<td>Question6	</td><td>2	</td><td>4</td></tr>
<tr>
<td>7</td>	<td>Question7</td>	<td>9	</td><td>4</td></tr>
<tr>
<td>1</td>	<td>Question1	</td><td>5</td>	<td>1</td></tr>
<tr>
<td>2</td>	<td>Question2	</td><td>9</td>	<td>1</td></tr>
<tr>
<td>3	</td><td>Question3	</td><td>5</td><td>	1</td></tr>
<tr>
<td>4</td>	<td>Question4</td>	<td>2	</td><td>1</td></tr>
<tr>
<td>5</td>	<td>Question5</td>	<td>5	</td><td>1</td></tr>
<tr>
<td>6</td>	<td>Question6</td>	<td>5	</td><td>1</td></tr>
<tr>
<td>7</td>	<td>Question7</td>	<td>2</td>	<td>1</td></tr>
<tr>
<td>1</td>	<td>Question1</td>	<td>2	</td><td>2</td></tr>
<tr>
<td>2</td>	<td>Question2</td>	<td>0	</td><td>2</td></tr>
<tr>
<td>3	</td><td>Question3</td>	<td>9	</td><td>2</td></tr>
<tr>
<td>4</td>	<td>Question4	</td><td>9</td><td>	2</td></tr>
<tr>
<td>5	</td><td>Question5	</td><td>9</td><td>	2</td></tr>
<tr>
<td>7	</td><td>Question7</td>	<td>5	</td><td>2</td></tr>
<tr>
<td>1</td>	<td>Question1</td><td>	2</td>	<td>4</td></tr>

</table>

＆＃13;

表C：

＆＃13;

<table>
<tr>
<th>Project ID</th>
<th>Question1</th>
<th>Question2</th>
<th>Question3</th>
<th>Question4</th>
<th>Question5</th>
<th>Question6</th>
<th>Question7</th>
</tr>
<tr>
<td>1000</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td>1005</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
</table>

＆＃13;

期望的结果（表C）：

＆＃13;

    <table>
    <tr>
    <th>Project ID</th>
    <th>Question1</th>
    <th>Question2</th>
    <th>Question3</th>
    <th>Question4</th>
    <th>Question5</th>
    <th>Question6</th>
    <th>Question7</th>
    </tr>
    <tr>
    <td>1000</td>
    <td>2</td>
    <td>5</td>
    <td>5</td>
    <td>5</td>
    <td>2</td>
    <td>2</td>
    <td>9</td>
    </tr>
    <tr>
    <td>1005</td>
    <td>2</td>
    <td>0</td>
    <td>9</td>
    <td>9</td>
    <td>0</td>
    <td>9</td>
    <td>5</td>
    </tr>
    </table>

＆＃13;

Answer 1

您想要更新表C的问题1，将值设置为等于从B中选择的Answer_weightage，其中b.Description =＆＃39; Question1＆＃39;和linkId =（来自A的Link_Id，其中最新的=＆＃39;是＆＃39;并且具有与C相同的projectId）。

Update C set C.Question1 =
 (select Answer_weightage
    from B
    where Description='Question1' and Link_ID =
         (select Link_ID
            from A
            where A.ProjectID = C.ProjectID and Latest='Yes'))

SQL更新查询通过连接3个表来获取值

1 个答案: