The values of some formats are determined by the value of initialization parameters.
For such formats, you can specify the characters returned by these format elements implicitly using the initialization parameter All number format models cause the number to be rounded to the specified number of significant digits.
is a character literal that describes the format of datetime or numeric data stored in a character string.
A format model does not change the internal representation of the value in the database.
When you convert a character string into a date or number, a format model determines how Oracle Database interprets the string.
In SQL statements, you can use a format model as an argument of the For lists of number and datetime format model elements, see Table 2-17, "Matching Character Data and Format Models with the FX Format Model Modifier" and Table 2-19, "Attributes of the XMLFormat Object".
The tables that follow list the elements of a number format model and provide some examples.
Negative return values automatically contain a leading negative sign and positive values automatically contain a leading space unless the format model contains the Returns value with the specified number of digits with a leading space if positive or with a leading minus if negative.Leading zeros are blank, except for a zero value, which returns a zero for the integer part of the fixed-point number.Returns negative value with a leading minus sign (-).Returns positive value with a leading plus sign (+).Returns negative value with a trailing minus sign (-).Returns positive value with a trailing plus sign (+).