HiRDB database supports Greatest function without ? parameters. SQLWays changes greatest function with arguments count more than 3 to greatest function with 3 arguments, which contains greatest functions.

Oracle:

SELECT GREATEST('HARRY', 'HARRIOT', 'HAROLD'), GREATEST('HARRY', 'HARRIOT', 'HAROLD', 'HOHO') FROM t; 

HiRDB:

SELECT GREATEST('HARRY','HARRIOT','HAROLD'), GREATEST('HARRY','HARRIOT', GREATEST('HAROLD','HOHO')) FROM t;

HiRDB hasn't equivalents for Greatest function with ? parameters. SQLWays leaves it as is and adds message /* This conversion has inappropriate possibility*/.

Oracle:

SELECT GREATEST('HARRY', 'HARRIOT', ?)  FROM t; 

HiRDB:

SELECT GREATEST('HARRY','HARRIOT', ? as datatype) FROM t;
/* This conversion has inappropriate possibility*/