Severity: error --> Exception: Call to a member function quote() ...

@imabot,

This is definitely not a CI issue.

Database type?MySQL? How often does this happen?  How do you connect to the database (localhost or by DSN)?  Have you researched to determine if this is a common issue?  PHP PDO version?

Database is MySQL. It happens about 1 times on 10,000. I'm using PDO to connect to the database, conventional CI PDO drivers.

Of course, I already made some researches about this error, but I didn't find any useful answers or even explanations. 

I bet that I'm not he only user affected by this problem, but probably that the others do not know it because, they don't check error log files ...