我需要做些什么来纠正这个SQL语句？

Question

我有以下表格：

1. products - 包含产品库存。
2. suppliers - 包含供应商详细信息。
3. product_category - 包含产品类别的名称。
4. product_suppliers - 包含产品和供应商之间的关系。

这里最重要的一个可能是，product_suppliers，所以这里的列：

id //(auto-increment) 
prod_id //(id of product) 
sup_id //(id of supplier) 
preferred //(1 if it's the preferred supplier for that product - 0 if not) 
cost_per_outer //(this suppliers price for this item) 
qty_in_outer //(the number in a box) 

的product表，其中存储产品的详细信息，也有stock_level和reorder_level的字段。当前者小于后者时，该产品应包括在重新排序列表中。

我想构建列表的查询，这是不正常工作。

我有4项符合重新排序影响两个供应商。每个供应商应该有两个项目，但目前它只是检索第一个供应商的结果。

我正在使用MySQL和PHP。

我已经运行下面的查询来给我们一些启示，以在数据库中的实际数据：

mysql> SELECT 
    ->   p.prod_id, 
    ->   AES_DECRYPT(p.alt_id, 'MW4KQLg1Irfo3Xz7Nxht')       AS sku, 
    ->   AES_DECRYPT(p.prod_name, 'MW4KQLg1Irfo3Xz7Nxht')      AS prod_name, 
    ->   AES_DECRYPT(p.prod_type, 'MW4KQLg1Irfo3Xz7Nxht')     AS prod_type, 
    ->   AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht')     AS stock_level, 
    ->   AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht')   AS reorder_level, 
    ->   AES_DECRYPT(c.category_name, 'MW4KQLg1Irfo3Xz7Nxht')   AS category_name, 
    ->   ps.sup_id, 
    ->   ps.preferred 
    -> FROM 
    ->   products p 
    -> INNER JOIN 
    ->   product_category c 
    -> ON 
    ->   p.category_id = c.category_id 
    -> INNER JOIN 
    ->   product_supplier ps 
    -> ON 
    ->   p.prod_id = ps.prod_id 
    -> INNER JOIN 
    ->   suppliers s 
    -> ON 
    ->   ps.sup_id = s.supplier_id 
    -> ORDER BY 
    ->   ps.sup_id; 
+---------+------+-----------------+-----------+-------------+---------------+---------------+--------+-----------+ 
| prod_id | sku | prod_name  | prod_type | stock_level | reorder_level | category_name | sup_id | preferred | 
+---------+------+-----------------+-----------+-------------+---------------+---------------+--------+-----------+ 
|  7 | 7 | Term Block  | 1   | 3   | 5    | Electrical |  2 |   1 | 
|  5 | 5 | Electrical Tape | 1   | 12   | 20   | Electrical |  2 |   1 | 
|  6 | 6 | BlowGas   | 1   | 6   | 15   | Plumbing  |  12 |   1 | 
|  1 | 1 | PTFE Tape  | 1   | 9   | 10   | Plumbing  |  12 |   1 | 
+---------+------+-----------------+-----------+-------------+---------------+---------------+--------+-----------+ 

下面是清单，结果只显示两个的四个项目我期待的查询：

mysql> SELECT 
    ->   p.prod_id, 
    ->   AES_DECRYPT(p.alt_id, 'MW4KQLg1Irfo3Xz7Nxht')       AS sku, 
    ->   AES_DECRYPT(p.prod_name, 'MW4KQLg1Irfo3Xz7Nxht')    AS prod_name, 
    ->   AES_DECRYPT(p.prod_desc, 'MW4KQLg1Irfo3Xz7Nxht')     AS prod_desc, 
    ->   AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht')    AS stock_level, 
    ->   AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht')    AS reorder_level, 
    ->   AES_DECRYPT(p.reorder_qty, 'MW4KQLg1Irfo3Xz7Nxht')    AS reorder_qty, 
    ->   p.vat_exempt, 
    ->   AES_DECRYPT(p.lastorderdate, 'MW4KQLg1Irfo3Xz7Nxht')   AS lastorderdate, 
    ->   AES_DECRYPT(p.lastorderqty, 'MW4KQLg1Irfo3Xz7Nxht')    AS lastorderqty, 
    ->   AES_DECRYPT(c.category_name, 'MW4KQLg1Irfo3Xz7Nxht')   AS category_name, 
    ->   ps.sup_id 
    -> FROM 
    ->   products p 
    -> INNER JOIN 
    ->   product_category c 
    -> ON 
    ->   p.category_id = c.category_id 
    -> INNER JOIN 
    ->   product_supplier ps 
    -> ON 
    ->   p.prod_id = ps.prod_id 
    -> INNER JOIN 
    ->   suppliers s 
    -> ON 
    ->   ps.sup_id = s.supplier_id 
    -> WHERE 
    ->   AES_DECRYPT(p.prod_type, 'MW4KQLg1Irfo3Xz7Nxht') = 1 
    -> AND 
    ->   AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht') <= AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht') 
    -> AND 
    ->   ps.preferred = 1 
    -> ORDER BY 
    ->   ps.sup_id; 
+---------+------+-----------------+------------------------+-------------+---------------+-------------+------------+---------------+--------------+---------------+--------+ 
| prod_id | sku | prod_name  | prod_desc    | stock_level | reorder_level | reorder_qty | vat_exempt | lastorderdate | lastorderqty | category_name | sup_id | 
+---------+------+-----------------+------------------------+-------------+---------------+-------------+------------+---------------+--------------+---------------+--------+ 
|  7 | 7 | Term Block  | Nylon connector block. | 3   | 5    | 20   |   0 | NULL   | NULL   | Electrical |  2 | 
|  5 | 5 | Electrical Tape | Black     | 12   | 20   | 100   |   0 | NULL   | NULL   | Electrical |  2 | 
+---------+------+-----------------+------------------------+-------------+---------------+-------------+------------+---------------+--------------+---------------+--------+ 

Answer 1

的问题是，你的结果是从AES_DECRYPT（）来了来了string型的，这就是为什么相比于stock_level和重新排序3 - 5和12 - 20它显示的电平值而6 -15和9 - 20它没有显示因为如果你comapre 6和15串6将超过15同样是9时和20

希望你有你的问题......

转换AES_DECRYPT（）可在数字前的结果比较..

您的where子句改成这样

WHERE 
    (AES_DECRYPT(p.prod_type, 'MW4KQLg1Irfo3Xz7Nxht') + 0) = 1 AND 
    (AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht') + 0) <= (AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht') + 0) 

添加+0将结果转换为数字

希望这有助于。

Answer 2

WHERE 
    ->   AES_DECRYPT(p.prod_type, 'MW4KQLg1Irfo3Xz7Nxht',varchar) = 1 
    -> AND 
    ->   AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht',varchar) <= AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht',varchar) 

或：

WHERE 
    ->   AES_DECRYPT(p.prod_type, 'MW4KQLg1Irfo3Xz7Nxht',int) = 1 
    -> AND 
    ->   AES_DECRYPT(p.stock_level, 'MW4KQLg1Irfo3Xz7Nxht',varchar) <= AES_DECRYPT(p.reorder_level, 'MW4KQLg1Irfo3Xz7Nxht',varchar) 

来自：http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.infocenter.dc01015.1510/html/iqsecure/Functions_s_4132405.htm

如果同时插入使用 AES_ENCRYPT函数的数据，你不使用CAST语句，你可以通过VARCHAR作为数据类型查看使用AES_DECRYPT 功能相同的数据。如果您未将 数据类型传递给AES_DECRYPT，则返回VARBINARY数据类型。