Manage events and manage event groups

I mean my wordpress itself is connecting a remote datebase,that’s the reason why I can’t get search result from manage events page and event search in the sidebar widget both.
If I use my wordpress itself to connect a local datebase,there is no such issue.

No, that shouldn’t make any difference at all. There’s nothing different about the search query from any other query in My Calendar. There may be something about your remote DB server that’s odd, but if you’re using WordPress to connect to a remote DB and not My Calendar’s facility for that, it’s just not any different.

Is that your set up? Wp-config set to a remote DB, and My Calendar using the normal DB?

Yes,Wp-config set to RDS,so My Calendar is using the same RDS without setting it on plugin.

It is odd too that I am able to search my posts from my wordpress since you believe my RDS is too odd to get the normal search query for My Calendar.

I don’t “believe [your] RDS is too odd” – I’m simply positing some kind of oddity in that database server as the cause of this issue. I really don’t have any information to go on, so all I can do is make guesses.

I can’t reproduce the issue.

Odd thing must got a particular reason.
When I search ‘test it’ on My Calendar,this SQL log generated on RDS

SELECT SQL_CALC_FOUND_ROWS * FROM wp_my_calendar WHERE event_flagged = 0 AND MATCH(event_title,event_desc,event_short,event_label,event_city) AGAINST ('test it' IN BOOLEAN MODE) AND event_status = 1 ORDER BY event_begin DESC LIMIT 0, 50

What is event_flagged for?
BTW,when I created events,wp_posts got all wp_my_calendar’s things,is this redundency necessary?

Event flagged indicates whether an event has been flagged as spam by Akismet or Botsmasher. Mostly applies to untrusted event authors, such as when using the My Calendar: Submissions add-on.

And yes, it is necessary to post to both wp_posts and to the my calendar table. Eventually, the My Calendar table will be made obsolete, but it’s still necessary for now.

Finally,I figured it out.
The wp_my_calendar on my RDS was using InnoDB storage engine which doesn’t support the My Calendar search query ‘MATCH’

SELECT SQL_CALC_FOUND_ROWS * FROM wp_my_calendar WHERE event_flagged = 0 AND MATCH(event_title,event_desc,event_short,event_label,event_city) AGAINST ('audience' IN BOOLEAN MODE) AND event_status = 1 ORDER BY event_ID DESC LIMIT 0, 20

I changed its storage engine to MyISAM

alter table wp_my_calendar engine=MyISAM

Now I am able to get search result from My Calendar,but only in English,Multi-byte like Korean,Japanese,Chinese doesn’t work.
I checked how wordpress itself get search result.Wordpress uses LIKE search query which is perfectly working on InnoDB or MyISAM storage engine

SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND (((wp_posts.post_title LIKE '%audience%') OR (wp_posts.post_content LIKE '%audience%'))) AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish' OR wp_posts.post_status = 'future' OR wp_posts.post_status = 'draft' OR wp_posts.post_status = 'pending' OR wp_posts.post_status = 'private') ORDER BY wp_posts.post_title LIKE '%audience%' DESC, wp_posts.post_date DESC LIMIT 0, 20

I would suggest you change My Calendar to ‘LIKE’ search query istead of ‘MATCH’

I’ll consider it, but in fact my goal is to make the My Calendar search obsolete, and replace it with the native search, along with making the my calendar events table obsolete. But it all depends on how long that takes me.

If I understand you correctly,I think you mean you want to keep My Calendar not seperated from wp_posts.Why?Is that bad to have wp_my_calendar?

Because it makes a lot of aspects of plug-in management vastly easier to use the WordPress native methods for managing data instead of using all custom methods. It means I can significantly reduce the amount of code I need to manage, write, and support, while taking advantage of all the features that are built into WordPress. As it is, there are many features built into WordPress that I would have to re-create in order to use.