Tonumber usage in oracle
The TO_NUMBER function in Oracle converts a string into a numeric value. It takes a string argument, with the optional format_mask specifying the number format in the string. It returns a value of type NUMBER, or NULL if the conversion fails.
TO_NUMBER function usage in Oracle
TO_NUMBER function is used to convert a string or text value into a numeric value. It is a built-in function widely used in data conversion and calculations.
Syntax:
<code>TO_NUMBER(string, [format_mask])</code>
Parameters:
- string: Characters to be converted String or text value.
- format_mask (optional): Specifies the mask for the format of numbers in the string. It follows SQL standard format notation.
Example:
Convert the string "123.45" to the number 123.45:
SELECT TO_NUMBER('123.45') FROM DUAL;
Parse the string "1,234.56" into a number 1234.56, mask "9G999G999" Specify thousands separator and two decimal points:
SELECT TO_NUMBER('1,234.56', '9G999G999') FROM DUAL;
Get a string value from the table and convert it to a number:
SELECT TO_NUMBER(column_name) FROM table_name;
Return type :
TO_NUMBER function returns a numeric value of NUMBER data type. If the conversion fails, it returns NULL.
Note:
- If the string contains non-numeric characters, the conversion will fail.
- The conversion will also fail if the format specified by format_mask does not match the number format in the string.
- TO_NUMBER function can be used to convert a string represented in scientific notation to a number.
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