dcsimg

Email Validation Function

October 9, 2003



>>Script Language and Platform: MSSQL
This function checks for invalid characters, and some basic format. Since SQL can't use regular expressions, it cannot do a thorough validation, but this function DOES handle the minimum. If the email is valid, it returns 1, if not 0.

*ex. This is to delete invalid emails

DELETE FROM address WHERE master.dbo.EMAILVALIDATE(email) = 0

Author: Jimmy Hattori


CREATE FUNCTION EMAILVALIDATE (@email varChar(100))
RETURNS int
AS
BEGIN
DECLARE @invalChars varchar(5),@valid int,@badChar varchar(1),@atPos
int,@periodPos int
SET @valid = 1
SET @invalChars = ' /:,;'
--Check to see if it's blank
IF len(ltrim(rtrim(@email))) = 0
   SET @valid = 0
ELSE
  	--Loop invalid characters to see if it exists in email
	WHILE len(@invalChars) > 0
	   BEGIN
		SET @badChar = substring(@invalChars,1,1)
		IF(charindex(@badChar,@email) > 0)
		   --If invalid character was found, return 0 to invalidate
		   SET @valid = 0
		SET @invalChars = replace(@invalChars,@badChar,'')
	   END
	--Check to see if "@" exists.
	SET @atPos = charindex('@',@email,1)
	IF @atPos = 0
	   SET @valid = 0
 	--Check to see if extra "@" exists after 1st "@".
	IF charindex('@',@email,@atPos+1) > 0
	   SET @valid = 0
	SET @periodPos = charindex('.',@email,@atPos)
	IF @periodPos = 0
	   SET @valid = 0
	IF (@periodPos+3) > len(@email)
	   SET @valid = 0
	RETURN (@valid)
END


Disclaimer: We hope that the information on these script pages is valuable to you. Your use of the information contained in these pages, however, is at your sole risk. All information on these pages is provided "as -is", without any warranty, whether express or implied, of its accuracy, completeness, or fitness for a particular purpose... Disclaimer Continued


Back to Database Journal Home








The Network for Technology Professionals

Search:

About Internet.com

Legal Notices, Licensing, Permissions, Privacy Policy.
Advertise | Newsletters | E-mail Offers