Why does this simple select statement require quotes?
You created your column with double quotes, so now Oracle requires you to always refer to this column using identifiers and respecting the case. If you remove the double quotes, Oracle always transforms the name to upper case, so without them it is case insensitive.

This will work if you created the column without identifiers:

where rulE_id
where RULE_ID


Also when creating a table, quotes are not required, unless you use reserved words.