如何显示两个mysql表中的所有记录而不显示空白记录？ [英] How to display all the records from two mysql tables without displaying blank record?

问题描述

尝试谷歌但没有成功。我正在使用php与mysql。我有两个表 - pm和pm_reply。我想显示这些表中的所有记录。我使用左连接来组合表。问题是如果pm有一行并且pm_reply为空，我从pm获取所有记录以及我认为来自pm_reply的空白记录。



现在请告诉我如何在没有此空白记录的情况下显示pm和pm_reply的所有记录。



这是我的下午表：

Tried google but no success. I am using php with mysql. I have two tables- pm and pm_reply. I want to display all the records from these tables. I am using left join to combine tables. Problem is if pm has a row and pm_reply is empty, i am getting all the records from pm along with blank record that is i think from pm_reply.

Now plz tell me how to display all the records from pm and pm_reply without this blank record.

Here is my pm table:

pm_id int not null primary key autoincrement,
subject varchar(50) not null,
message text not null

这里是pm_reply表：

And Here is pm_reply table:

pm_reply_id int not null primary key autoincrement, 
pm_id int not null,
resubject varchar(50) not null,
details text not null

这是我的查询：

And here is my query:

$sql=mysql_query("select pm.*,  pm_reply.* FROM pm LEFT JOIN pm_reply ON pm.pm_id=pm_reply.pm_id" );

推荐答案

sql = mysql_query（ select pm。*，pm_reply。* FROM pm LEFT JOIN pm_reply ON pm.pm_id = pm_reply.pm_id）;

sql=mysql_query("select pm.*, pm_reply.* FROM pm LEFT JOIN pm_reply ON pm.pm_id=pm_reply.pm_id" );

也许这可能会有所帮助

mysql左连接说明 [ ^ ]



您是否尝试过没有LEFT关键字？

Maybe this can be of help
mysql left join explanation[^]

Have you tried without the LEFT keyword?

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