Create unique case-insensitive constraint on a column.
Solution: Add function level unique index, example –
CREATE UNIQUE INDEX index_name on table_name (UPPER(Column_Name));

Cannot create service/sid using ORADIM (DIM-00019: create service error O/S-Error: (OS 5) Access is denied.)
Solution: Make sure your oracle service is running. then create instance.
To create instance- Open CMD (command prompt) with admin privilege. the type the following then hit enter.

ORADIM -NEW -SID SID_NAME

Custom success message: APEX
apex_application.g_print_success_message := '<span style="color:green">Computer created</span>';