ORA-00918 also referred to as an ORA 918 is a common issue/error that occurs during the development of queries through joins of multiple tables and other issues listed below.  Most of the time an Ora-00918 occurs due to the fact that a column with the same name exists in both tables. Another not so well documented reason for this issue to occur is the initial definition of views using a "select *" followed by addition of columns to the underlying table.

ORA-7445  is a critical error generated by an oracle database when it has receives a fatal signal from the operating system. This error may be raised in either a foreground or background process.  The most common reason for this error is where a pointer in memory is overwritten in error by a software problem. In this event, when the pointer is used to lookup the data it is pointing at, this may likely reference an area of memory without the process address space. Read more about the cause, interpretation and resolution of the error below..

Oracle RDBMS Kernel raises an ORA-00600 error when an unexpected condition is met during its normal functioning. An ORA-00600 oracle error may not necessarily be a bug all the time and could be caused due to various reasons. Oracle error 600 reasons can include a Lack of System Resources, Operating System Issues, Hardware Failures and many other dependent system driver issues. In many instances, ORA-00600 error indicates an existing corruption in the oracle database or can be a indication of events leading to data or database corruption.Oracle database administrators should take an ORA-00600 error very seriously and work with oracle support to resolve this issue.

ORA-12560 Oracle error indicates a high level error that may have happened in the oracle sqlnet or net8 transport layer. The actual error should be identified based on the other messages that oracle has displayed along with the ORA-12560 error message