Looking for a function to using IF ELSE condition in MYSQL - mysql

Question

I have a table data with combination of Integer and strings. Like this
CREATE TABLE EMPLOYEE (
empId INTEGER,
name TEXT NOT NULL,
email TEXT NOT NULL,
phone TEXT NOT NULL
);
INSERT INTO EMPLOYEE VALUES (12345, 'Clark Duff', 'Sales#yahoo.com',9001234567);
INSERT INTO EMPLOYEE VALUES (22245, 'Dave Johnson', 'Accounting#gmail.com',9000123456);
INSERT INTO EMPLOYEE VALUES (55456, 'Ava evelene', 'Sales_Marketing#gmail.com',9000012345);
But I'm looking for a common function in MYSQL to check the condition whether it is a special character or integer or string. Below syntax will mask the data:
If it is an integer then this condition needs to execute:
concat(SUBSTRING(phone,1,3) , '*****' , SUBSTRING(phone,7,4)) phone
If it is a special character (#) then this condition needs to execute:
CONCAT(LEFT(UUID(), 8), '#', SUBSTRING_INDEX(`Mail`, '#', -1)) as Mail
ELSE string then other script

Answer 1

seem you are looking for case statement applied to like condition for # char or cast to usingned for chekc a valid integer number
select case
when email like '%#%' then CONCAT(LEFT(UUID(), 8), '#', SUBSTRING_INDEX(`Mail`, '#', -1))
when cast(phone AS UNSIGNED) != 0 THEN concat(SUBSTRING(phone,1,3) , '*****' , SUBSTRING(phone,7,4))
else 'not managed'
end

Answer 2

One UDF to mask them.
CREATE FUNCTION fnMaskUserInfo (
input TEXT
)
RETURNS TEXT
DETERMINISTIC
BEGIN
IF input LIKE '%_#_%._%'
THEN
RETURN CONCAT(RIGHT(SHA1(input),8),'#',SUBSTRING_INDEX(input,'#',-1));
END IF;
IF input REGEXP '^[0-9]{7,10}$'
THEN
RETURN CONCAT(SUBSTRING(input,1,3),'*****',SUBSTRING(input,7,4));
END IF;
RETURN input;
END
SELECT empId
, fnMaskUserInfo(Name) AS Name
, fnMaskUserInfo(email) AS email
, fnMaskUserInfo(phone) AS phone
FROM EMPLOYEE
empId
Name
email
phone
12345
Clark Duff
1beb980f#yahoo.com
900*****4567
22245
Dave Johnson
1dadfff9#gmail.com
900*****3456
55456
Ava evelene
3a0768e7#gmail.com
900*****2345
Demo on db<>fiddle here

Answer 3

Here is an example stored function. Is this what you mean?
CREATE FUNCTION `someFunc`(
input VARCHAR(255)
)
RETURNS VARCHAR(255)
NOT DETERMINISTIC
BEGIN
IF input LIKE '%#%' THEN
RETURN CONCAT(LEFT(UUID(), 8), '#', SUBSTRING_INDEX(input, '#', -1));
ELSEIF input REGEXP '^[0-9 ]{7,10}$' THEN
RETURN CONCAT(SUBSTRING(input, 1, 3) , '*****' , SUBSTRING(input, 7, 4));
ELSE
RETURN input;
END IF;
END
You may want to use LEFT(MD5(input), 8) instead of LEFT(UUID(), 8) so that the function can be declared as deterministic.
CREATE FUNCTION `someFunc`(
input VARCHAR(255)
)
RETURNS VARCHAR(255)
DETERMINISTIC
BEGIN
IF input LIKE '%#%' THEN
RETURN CONCAT(LEFT(MD5(input), 8), '#', SUBSTRING_INDEX(input, '#', -1));
ELSEIF input REGEXP '^[0-9 ]{7,10}$' THEN
RETURN CONCAT(SUBSTRING(input, 1, 3) , '*****' , SUBSTRING(input, 7, 4));
ELSE
RETURN input;
END IF;
END
WITH `EMPLOYEE` (`empId`, `name`, `email`, `phone`) AS (
SELECT 12345, 'Clark Duff', 'Sales#yahoo.com',9001234567 UNION
SELECT 22245, 'Dave Johnson', 'Accounting#gmail.com',9000123456 UNION
SELECT 55456, 'Ava evelene', 'Sales_Marketing#gmail.com',9000012345
)
SELECT
empId,
someFunc(`name`) AS `name`,
someFunc(`email`) AS `email`,
someFunc(`phone`) AS `phone`
FROM `EMPLOYEE`;
# empId
name
email
phone
12345
Clark Duff
b3282336#yahoo.com
900*****4567
22245
Dave Johnson
47c44ab0#gmail.com
900*****3456
55456
Ava evelene
ab3fee5c#gmail.com
900*****2345