After restore of database backup, question marks appear randomly in many pages

That’s a well-known issue, at least when you’ve seen it a few times before.

For a bit if technical background, the database engine (MySQL) stores the data in a particular format, or ‘collation’ as they call it. That can change between servers, and even within databases, so it’s a little bit too fluid, but it’s needed to account for a the wide array of non-English languages that the database needs to support.

What’s happened is that when the content was restored, the collation was different on the new server to what it was on the old server, so while the data is the same, because it’s being “transferred” through a different collation, some characters are affected and change to something else.

You’ll probably see that everything that’s affected are things like ‘, ” and other punctuation. It doesn’t normally affect standard English letters much.

There’s only two fixes for it. First, set the collation on the new database to match the old one. That could cause some issues, so make sure you have backups of everything before you even think of that! The second one is to go through everything manually and update the broken characters to what they should be. You might be able to use a good search-and-replace plugin for that, but again, take a backup before you do anything.

• This reply was modified 6 years, 1 month ago by catacaustic.

I appreciate your clear response.

I use 2 different types of database backup files.
1 is direct from wordpress dashboard
ENGINE=MyISAM AUTO_INCREMENT=4888 DEFAULT CHARSET=latin1 ;
1 is direct from cpanel
ENGINE=MyISAM AUTO_INCREMENT=4341 DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

I have also changed my database wp posts table to collate to utf8_general_ci

But it doesn’t seem to work.

Your second fix is very tedious involving 1000+ posts.

First, set the collation on the new database to match the old one.
Do I get you correct? I need to create a new database and move everything from old to new?

I haven’t had to do it before, everything that I’ve seen that problem on was a small enough site that it wasn’t worth trying to do it like that, so things were done manually.

I would think that it’s worth trying to see how it goes. If it works it’s by far the easiest solution.

Do you provide any service to solve my problem? Thank you.

No, I don’t do anything like that, sorry.

Also, just to make a small point – Asking for, or offering, services on this forum isn’t something that goes down too well with the moderators. It’s best that you try other places if you’re thinking of hiring help for this.