Well I don’t think it would be
\\\\n but just
\\n, the thing is, you want to query the database by the post id, so you can view its content to potentially identify what could be wrong in it.
If you had to run a query to update it, it would be something like:
UPDATE `Posts` SET `Message` = REPLACE(`Message`,'\\n', CHAR(10)) WHERE `ChannelId` = 'id';
CHAR(10) is a line feed.
Also, since you’re using
LIKE, you would need to use % at the begin and end of it, since you do not know where the literal string is located at, inside the message:
SELECT * FROM Posts WHERE ChannelId = 'id' AND Message LIKE '%\\n%';