格式:TO_CHAR(number,'format_model')
9 -->Represents a number
0 --> Forces a zero to be displayed
. -->Prints a decimal point
, --> Prints a comma as a thousands indicator
select to_char(6000,'99,999.00') from dual;
6,000.00
select to_char(6000,'00,000.00') from dual;
06,000.00