select TO_CHAR(1000, '9,999') from dual
select TO_CHAR(1.1, '99.99') from dual
--> 1.10
select TO_CHAR(10.1, '099.99') from dual
--> 010.10
select TO_CHAR(0, '0.99') from dual
--> 0.00
select TO_CHAR(15, '0000') from dual
--> 0015
select TO_CHAR(0,'99') from dual
--> 0
select TO_CHAR(0,'99.9') from dual
--> .0
select TO_CHAR(0,'90.9') from dual
--> 0.0
select TO_CHAR(0,'B99') from dual
--> 空白
select TO_CHAR(0,'B99.9') from dual
select TO_CHAR(5,'B99.9') from dual
--> 5.0
select TO_CHAR(1,'S99') from dual
--> +1
select TO_CHAR(1,'99S') from dual
--> 1+
select TO_CHAR(0,'S99') from dual
--> +0