How do you write such a sql?

add the following two tables
comment to record comments and comments 

CREATE TABLE `comment` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `comment` varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
)

the reply_to table records the relationship between replies and comments 

CREATE TABLE `reply_to` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `response_id` int(11) NOT NULL, //idcommentid
  `comment_id` int(11) NOT NULL, //idcommentid
  PRIMARY KEY (`id`)
)

Table comment data is as follows

clipboard.png
reply_to

clipboard.png

()sql

https://stackoverflow.com/que...
sql

clipboard.png
(~):

clipboard.png

Mysql sql
Aug.20,2021
There is a problem with the design of the

table. The relationship between comments and responses is one-to-many, so there is no need for relational tables.

comment form comment
comment_id,text

reply table reply
reply_id,comment_id,reply_text

query
SELECT * FROM comment LEFT JOIN reply ON comment.comment_id = reply.comment_id

take a look, the first sql in the answer is correct, but no unanswered comments can be displayed. So it's good to rewrite it with outer join, but when you make a mistake, no one notices it. Then I am more supportive of putting it in a table.
the correct rewrite sql is: 

SELECT
    c. COMMENT ,
    r. COMMENT AS reply
FROM
    `comment` c
LEFT OUTER JOIN reply_to rt ON c.id = rt.comment_id
LEFT OUTER JOIN `comment` r ON rt.response_id = r.id

Previous: Problems with the display of insert query update delete getmore command field values in mongostat

Next: How is the LDNS function of 17CE implemented?

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e548cb-452c5.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1e548cb-452c5.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?