SQL query to display records from multiple tables

I have following two tables

1. Table name: thread

   pk-> thread_id | thread_title | description | posted_time | Subject

2. Table name: reply

   pk-> reply_id | thread_id | reply

thread_id is fk

I want to c开发者_运维知识库ount no of replies on each thread, I want output like

thread_id | thread_title | description | posted_time | Subject | No_of_replies

Here's the query I've quickly come up with off of the top of my head:

SELECT
    T.Thread_ID
    ,T.Thread_Title
    ,T.Description
    ,T.Posted_Time
    ,T.Subject
    ,COUNT(R.Reply_ID) AS No_of_replies
FROM
    Thread T
    INNER JOIN Reply R ON T.Thread_ID = R.Thread_ID
GROUP BY
    T.Thread_ID
    ,T.Thread_Title
    ,T.Description
    ,T.Posted_Time
    ,T.Subject

This should do what you want.

select t1.*,ifnull(t2.no_of_replies) from thread t1 left join 
(select thread_id,count(1) no_of_replies from reply)t2
on t1.thread_id=t2.thread_id