cannot connect to database as it needs to be compiled.

Give a try if you are able to use DBCompiler.exe to compile. 

Hi, were you able to get this to work?  I'm having same issue after migrating a database and was curious if you were able to resolve.  Thanks,

Hi all,

This is happening due to DB ID being different, and the other tools (Manager, OB, Designer, etc.) are erroring out because they can't find the compiled code to run. 

Use DBCompiler.exe in order to connect to DB and generate new ID for it, this should allow you to compile the database. Then you should not have this error while connecting with other tools. 

Hope this helps.

Yuri

Steps to fix-

Step 1: Get In Touch With Your Web Host Provider. 
Step 2: Check If Your Plugin or Theme Files Haven't Been Corrupted. 
Step 3: Check If Your Database Hasn't Been Corrupted.
Step 4: Check Your Database Connection Credentials. 
Step 5: Restore The Default WordPress Files.

Regards,

Rachel Gomez