clear command - terminals database is inaccessible

Path for Anaconda3 is set in .bashrc. It is interfering with clear command. Removing Anaconda path from path solved the issue. Here is the github reference for the issue https://github.com/ContinuumIO/anaconda-issues/issues/331


You might have moved the anaconda directory after installation and some bash script links in some files from anaconda directory are still pointing to the previous location. Simplest solution is to delete your current anaconda installation directory, remove any paths in .bashrc pointing to it and reinstall it in the desired location.