PHP Warning: Attempt to read property "connect_error" on null

I just switched to a new server and I am able to view the tables and use the server behaviors but once I try and go into the query builder it gives me errors and i can not use it.
I was able to check the error log and this is what is in the log

[06-Jun-2023 06:03:46 UTC] PHP Warning: Attempt to read property "connect_error" on null in /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/mysql.php on line 382
[06-Jun-2023 06:03:46 UTC] PHP Fatal error: Uncaught TypeError: mysqli_errno(): Argument #1 ($mysql) must be of type mysqli, null given in /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/mysql.php:386
Stack trace:
#0 /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/mysql.php(386): mysqli_errno(NULL)
#1 /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/mysql.php(116): MySqlConnection->HandleException()
#2 /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/MMHTTPDB.php(123): MySqlConnection->TestOpen()
#3 {main}
thrown in /home1/bemsltpmicro/src.bems.ltpmicro.com/_mmServerScripts/mysql.php on line 386

That is usually an issue with your Dreamwever server settings. Can you send a screenshot of your testing server configuration? or better yet privately attach a copy of your site definition and i can reproduce and debug the problem directly.

I figured it out!
It seems when it would try and makethe connection.the files inside the _mmserver folder would get deleted and replaced. But it would never replace the MMHTTPDB.php file after everything was done. So I changed the permissions on that file and none of the files get deleted and it works

Ansd I changed the settings on the query dialog box to large and all the tables show up

As you mention you have switched to a new server and now you getting error message this happening due to change in PHP version. Now you have to update code according to latest PHP version or you need to revert older PHP version as was in previous server.