Question

我有一个数据库表cranedetails（字段为：cf_did , cf_firstname, cf_cranetype）

cf_did   cf_firstname     cf_cranetype 
1        Alexy            2,3    
2        Thomas           11,6,3  
3        Thomas           5,6,11,3        
4        Thomasxc         1,6,9,4         
5        Thomaseg         11,12,3

我有另一个表格类型（cf_did,cf_cname）

cf_ctid     cf_ctname
   1       MOBILE CRANES
   2       ROUGH TERRAIN CRANES
   3       ALL TERRAIN CRANES
   4       CRAWLER CRANES
   5       YARD CRANES
   6       ARICULATING BOOM CRANES
   7       TRUCK CRANES: ARTICULATING BOOM
   8       TRUCK CRANES: LATTICE BOOM
   9       TRUCK CRANES: TELESCOPIC BOOM
   10      TRUCK LOADER CRANES
   11      ELEVATORS
   12      ELEVATOR – HYDRAULIC

我想显示这样的值，例如：

id:    name:        cranetype

1      Alexy       ROUGH TERRAIN CRANES,ALL TERRAIN CRANES
2      Thomas      ELEVATORS,ARICULATING BOOM CRANES,ALL TERRAIN CRANES

等等。

如何从表格cf_cranetype 2,3（粗糙地形起重机，所有地形起重机）获取表起重机字段cranetype值{（1}}）字段。

我是教派$ did = 1。并使用此代码

cf_ctnamefield

但输出是：

$sql=mysql_query("SELECT * FROM `cf_directory` WHERE `cf_did` = '$did'",$con);
$row = mysql_fetch_array($sql);$cn= $row['11']; 
$sql2=mysql_query("SELECT * FROM  `cf_cranetype`  WHERE `cf_ctid`= '$cn'",$con);
<?php  while($row2 = mysql_fetch_array($sql2)){
     $cranename=$row2['cf_ctname']; ?>
<?php echo $cranename;?>

我想：

id:    name:        cranetype

1      Alexy       ROUGH TERRAIN CRANES

Answer 1

您只需GROUP_CONCAT()与FIND_IN_SET()一起使用即可：

SELECT
    cd.cf_did AS id,
    cd.cf_firstname AS name,
    GROUP_CONCAT(ct.cf_ctname SEPARATOR ', ') AS cranetype
FROM
    cranedetails cd,
    cranetype ct
WHERE
    FIND_IN_SET(ct.cf_ctid, cd.cf_cranetype)
GROUP BY
    cd.cf_did,
    cd.cf_firstname

输出是：

+----+----------+---------------------------------------------------------------------------------------+
| id | name     | cranetype                                                                             |
+----+----------+---------------------------------------------------------------------------------------+
|  1 | Alexy    | ROUGH TERRAIN CRANES, ALL TERRAIN CRANES                                              |
|  2 | Thomas   | ARICULATING BOOM CRANES, ELEVATORS, ALL TERRAIN CRANES                                |
|  3 | Thomas   | ALL TERRAIN CRANES, YARD CRANES, ARICULATING BOOM CRANES, ELEVATORS                   |
|  4 | Thomasxc | CRAWLER CRANES, ARICULATING BOOM CRANES, TRUCK CRANES: TELESCOPIC BOOM, MOBILE CRANES |
|  5 | Thomaseg | ALL TERRAIN CRANES, ELEVATORS, ELEVATOR – HYDRAULIC                                   |
+----+----------+---------------------------------------------------------------------------------------+
5 rows in set

如果您只想按名称对结果进行分组（因为存在重复的名称），只需从查询中删除cd.cf_did并添加DISTINCT即可过滤重复的cranetype值，即：

SELECT
    cd.cf_firstname AS name,
    GROUP_CONCAT(DISTINCT ct.cf_ctname SEPARATOR ', ') AS cranetype
FROM
    cranedetails cd,
    cranetype ct
WHERE
    FIND_IN_SET(ct.cf_ctid, cd.cf_cranetype)
GROUP BY
    cd.cf_firstname

结果将是：

+----------+---------------------------------------------------------------------------------------+
| name     | cranetype                                                                             |
+----------+---------------------------------------------------------------------------------------+
| Alexy    | ROUGH TERRAIN CRANES, ALL TERRAIN CRANES                                              |
| Thomas   | ELEVATORS, ALL TERRAIN CRANES, YARD CRANES, ARICULATING BOOM CRANES                   |
| Thomaseg | ELEVATORS, ELEVATOR – HYDRAULIC, ALL TERRAIN CRANES                                   |
| Thomasxc | TRUCK CRANES: TELESCOPIC BOOM, MOBILE CRANES, CRAWLER CRANES, ARICULATING BOOM CRANES |
+----------+---------------------------------------------------------------------------------------+
4 rows in set

Answer 2

使用子查询获取此参考http://dev.mysql.com/doc/refman/5.7/en/subqueries.html

Answer 3

对我来说，看起来你正在存储一个由逗号连接的整数值（你的cranetype id）的字符串值（或VARCHAR）。

如果是这样，我会考虑重新设计你的数据库，以便有一个表格，例如

起重机名称，cf_nid，cf_firstname
使用cf_ctid cf_ctname
起重机细节与cf_did，cf_nid，cf_ctid

在起重机细节中，为与起重机名称相关的每种起重机类型输入一个条目。 cf_nid和cf_ctid当然应该是与各个表的外键关系。

使用您当前的设计，您必须爆炸cf_cranetype的字符串值以获取整数数组（或字符串，看起来像整数），并且您的第二个查询必须如下所示： "SELECT * FROM cf_cranetype WHERE cf_ctid IN '" . join($YOUR_ARRAY, ',') . "'"

如何使用php从另一个表中获取一个表字段值

3 个答案: