Converts a given number to a string with a specified format
The following are format elements for the to_char function
9 : Outputs value with the specified number of digits. If there is no number, it returns blank space.
0 : Outputs value with the specified number of digits. It there is no number, it returns a zero.
. : Outputs a decimal point, which is a period (.) in the specified position
, : Outputs a comma (,) in the specified position
s : Outputs the value with plus sign (+) or minus sign (-). If it (S) is specified in the first position of a number format model, it outputs the value with a leading sign.
If it's specified in the last position, it outputs the value with a trailing sign.
mi : If the value is negative, it outputs negative value with a trailing minus sign (-)
pr : If the value is negative, it outputs negative value in
eeee : Outputs number with fixed‐point part and two digit exponent part. Before 'e', it outputs fixed-point part. After 'e', it outputs plus (+) or minus (-) sign and exponential part.