从表中选择字段，其中id不在mysql的另一个表中[不工作]

Question

我试图从表中获取数据，而该ID不在另一个表中。我引用了一些代码示例来解决这个问题，但它仍然无法正常工作。我尝试了两种风格。我试过的sql代码如下，请帮助我。感谢。

样式1

SELECT *
FROM quotation q
WHERE q.quotationId NOT IN (SELECT ip.quotation_id FROM invest_project ip)

样式2

SELECT *
FROM quotation q
LEFT JOIN invest_project ip
ON q.quotationId = ip.quotation_id
WHERE q.quotationId IS NULL

Answer 1

尝试不带别名......

$(document).ready(function() {

            var imgSrc = $("img").attr("src");
            alert(imgSrc);
});

Answer 2

当指定条件不显示空值数据时 试试这个

for card in computer_hand[:]:

Answer 3

Select *  
from [Table1] AS T1  
where not exists( select * from [Table2] AS T2 where T1.ID = T2.ID)  

这为我工作