查询2张表并输出
整个情况是这样的:
A表结构
id name info
1 栏目一 (存储样式为a:{s:6:"picid";s:2:"74";s:9:"text";s:1:"存储内容区";})
2 栏目二 (存储样式为a:{s:6:"picid";s:2:"75";s:9:"text";s:1:"存储内容区";})
B表结构
id url
74 图片路径
首先通过查询获取到了A表info中picid的id号为74,75的数组
输出样式为:
Array
(
[0] => 74
[1] => 75
)
然后在查询B表id为74,75的数据
然后如何关联输出这2张表的内容呢?
输出结果如何为:
Array
(
[0] => Array
(
[id] => 1
[name] => 栏目一
[url] => 图片路径
[info] => info中text的内容
)
[1] => Array
(
[id] => 2
[name] => 栏目一
[url] => 图片路径
[info] => info中text的内容
)
....
------解决方案--------------------
取出 info 中的 text 的内容的表达式
substring_index(substring_index(substr(info, locate('"text"', info)), '"', 4), '"', -1) as info
两表的关联条件
B表.id = substring_index(substring_index(substr(info, locate('"picid"', info)), '"', 4), '"', -1)
表达式很长,你可以用存储过程来缩短他
原理很简单
a:{s:6:"picid";s:2:"74";s:9:"text";s:1:"存储内容区";}
substr(info, locate('"picid"', info)) 用于取得 "picid" 看是的一段
"picid";s:2:"74";s:9:"text";s:1:"存储内容区";}
内层的 substring_index 用于取得 " 第4次出现以前的内容
"picid";s:2:"74
外层的 substring_index 用于取得 " 最后一次出现以后的内容
74

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