Comparing strings in sql I have a list of string values for example ('a', 'b', 'c', 'd', 'e'). Now I have a database lets say (T1) having two columns for example (user and permission). Every user has some permissions. For example.
|user   | permission|
| user1 | a         |
| user2 | a,b,f     |
| user3 | b,c       |
| user4 | e,d       |
| user5 | f,g       |

I want to write a query which can retrieve the users who are using those permissions. What I tried until now is below.
select * from T1 where permissions IN ('a', 'b', 'c', 'd', 'e')
After running this I only get user1 nothing else. But the answer should be user2 and others also because they are using permission a also.
Note: This is just an example. The strings I have are more than 25 and the database has more than 100 values.
What you can do is something like this (see the fiddle here):
Table:
CREATE TABLE t
(
  user VARCHAR (10) NOT NULL,
  permission VARCHAR (10) NOT NULL
);

Data:
INSERT INTO t VALUES
('user1', 'a'),
('user2', 'a, b, f'),
('user3', 'b, c'),
('user4', 'e, f'),
('user5', 'f, g');

Query:
SELECT * FROM t
WHERE permission LIKE '%a%'
OR    permission LIKE '%b%'
OR    permission LIKE '%c%'
OR    permission LIKE '%d%'
OR    permission LIKE '%e%';

Result:
user    permission
user1   a
user2   a, b, f
user3   b, c
user4   e, f

user5  is excluded because his permissions are 'f,g' and these don't appear in the sequence a-e.
p.s. welcome to the forum!