Syntax:
STR ( float_expression [ , length [ , decimal ] ] )Microsoft defines the function as “Returns character data converted from numeric data. The character data is right-justified, with a specified length and decimal precision.” The key words are “right -justified” and “specified length and decimal precision”. Let us go through an example to understand these two terms.
Select '*'+ str(1) + '*' Value,Len(str(1)) Value_Len

Few more interesting observations:
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1. By default, if the value is more than 10, then the value of the result is masked to “*” to 10 times.
2. If the length is specified, and the value is more than specified length, then again it masks to specified length.

Round up funda:
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1. If length is not specified, then depending the decimal part, the number is rounded to next.
2. Adds more 0 to match the decimal part, if in short the number for decimal.
