Can i drop the "APEX_050100" user in my DB to change TIME_ZONE?

Summary

Can i drop the "APEX_050100" user in my DB to change TIME_ZONE?

Content

Hello experts,

 

I'm using DBCS 11.2.0.4

 

Today i noticed that DB time zone is "+00:00".

We are in Cairo/Egypt so it should be "+02:00"

 

When i tried to alter using (alter database set TIME_ZONE = '+02:00';) it showed error:

ORA-30079: cannot alter database timezone when database has TIMESTAMP WITH LOCAL TIME ZONE columns.

 

Since i'm sure i'm not using this in my DB i issued this query to find where am i using this:

select owner, table_name

from   dba_tab_columns

where  data_type like 'TIMESTAMP%WITH LOCAL TIME ZONE';