如何SELECT FROM..WHERE然后在SQL中加入？

Question

我想从表中匹配状态＆＃39;的所有记录中选择as＆＃39;打开＆＃39;，然后执行与另一个表的左连接。我试过这个，但它不起作用：

SELECT (ticket.* WHERE ticket.status = 'Open'), ticketupdate.updatetime
FROM ticket
INNER JOIN ticketupdate ON ticketupdate.ticketid = ticket.ticketid

Answer 1

很简单，您可以使用where子句

进行左连接

select tk.*, tu.updatetime 
from ticket tk 
left join ticketupdate tu on tu.ticketid  = tk.ticketid 
where tk.status = 'Open';

Answer 2

您可以放入嵌套的SELECT

SELECT ticket.* , ticketupdate.updatetime
FROM (SELECT * FROM ticket WHERE status = 'Open') AS ticket
LEFT JOIN ticketupdate 
    ON ticketupdate.ticketid = ticket.ticketid