tech on the net

Oracle/PLSQL: Test a string for an alphabetic value

Question: In Oracle, I want to know if a string value contains alphabetic characters only. How can I do this?

Answer: To test a string for alphabetic characters, you could use a combination of the LENGTH function, TRIM function, and TRANSLATE function built into Oracle.

You can use the following command:

LENGTH(TRIM(TRANSLATE(string1, 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ' ')))

string1 is the string value that you are testing

This function will return a null value if string1 is alphabetic. It will return a value "greater than 0" if string1 contains any non-alphabetic characters.

For example,

LENGTH(TRIM(TRANSLATE('Tech3', 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ' '))) would return 1
LENGTH(TRIM(TRANSLATE('Tech1Net2', 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ' '))) would return 2
LENGTH(TRIM(TRANSLATE('Tech on the Net', 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ' '))) would return null

Learn more about the TRANSLATE function.

Learn more about the LENGTH function.

Learn more about the TRIM function.