Oracle conditional statements
In Oracle, empty string '' when assigned to a varchar2 type is NULL for all intents and purposes. In my SQLdeveloper, on a 12c database, the following query results in a (null) for every column. If you display to user a blank (a space, ' ') it would surely be displayed by all tools as a blank.

SELECT NULL, '', CAST('' as varchar2(1)), CAST('' as char(1)), NVL(null,'') FROM dual;


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