SELECT查询具有多个表的多列 [英] SELECT query for multiple column with multiple table

问题描述

我附上一张我的问题的图片:

I attach one image of my problem:

1. 在测试jFrame jTextField中，我将插入客户ID，然后按ok按钮后查询将选择并收集与该客户有关的信息.然后它将显示在jTableModel中.
2. 我附上我的数据库图像.
3. 错误是无法执行SQL代码".

推荐答案

您需要正确地连接表.
像这样:

You need to join the tables properly.
Like this:

SELECT
   paper_list,monday,tuesday,wednesday,thrsday,friday,saturday,sunday,magzine_name,rate 
FROM papers

LEFT JOIN papers_rate
    ON papers_rate.paperId = papers.id

LEFT JOIN magzines
     ON magzines.paperId = papers.id

LEFT JOIN magzines_rate 
     ON magzines_rate.magazineId = magzines.id

WHERE customer_id = ?"

如果您进行内部联接，例如，如果您没有magazine_rate，那么所有结果都将消失...

If you do an inner join, all your results will vanish if you don't have a magazine_rate for example...

并检查您的拼写.
您是在写 thrsday 而不是星期四，并写 magzine 而不是杂志...

And check your spelling.
You're writing thrsday instead of thursday and magzine instead of magazine...

PS:customer_id来自哪里?

PS: And where does customer_id come from ?

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