Oracle provides multiple methods to convert strings to numbers: TO_NUMBER function: Convert strings to numeric types using the specified format model. NUMTOSTR function: Converts a string to a numeric type and back to a string. VAL function: directly converts a string to a numeric type without checking the format.
How to convert a string to a number
Convert a string to a number in Oracle
Oracle provides a variety of methods to convert strings to numbers:
1. TO_NUMBER function
TO_NUMBER function converts strings to numeric types . It has the following syntax:
<code>TO_NUMBER(string, format_model)</code>
Where:
For example:
<code>SELECT TO_NUMBER('12345') FROM dual;</code>
Output:
<code>12345</code>
2. NUMTOSTR function
NUMTOSTR The function converts a string to a numeric type and converts the result to a string. It has the following syntax:
<code>NUMTOSTR(string)</code>
Where:
For example:
<code>SELECT NUMTOSTR('12345') FROM dual;</code>
Output:
<code>12345</code>
3. VAL function
VAL The function converts a string to a numeric type, but unlike the TO_NUMBER function, it does not perform any format checking. It has the following syntax:
<code>VAL(string)</code>
Where:
For example:
<code>SELECT VAL('12345X') FROM dual;</code>
Output:
<code>12345</code>
Note: VAL function for characters that contain non-numeric characters Strings may be unreliable. In this case, it is better to use the TO_NUMBER function.
The above is the detailed content of How to convert string to number in oracle. For more information, please follow other related articles on the PHP Chinese website!