Check whether a string is palindrome or not in PL/SQL

Prerequisite – PL/SQL introduction
In PL/SQL code groups of commands are arranged within a block. A block group related declarations or statements. In declare part, we declare variables and between begin and end part, we perform the operations.

Given a string and the task is to find whether it is Palindrome or not.
Examples:

Input: str = geeksskeeg
Output: geeksskeeg is palindrome

Input: str = geeks
Output: geeks is not palindrome

Approach is to take the string, reverse it and check whether the reversed string is equal to the original string or not. If it is equal, then it will be palindrome otherwise not.

Below is the required implementation:

DECLARE

    -- Declared variables are s, l, t .
    -- These variables are of same data type VARCHAR.
    s VARCHAR2(10) := 'abccba';
    l VARCHAR2(20);
    t VARCHAR2(10);
BEGIN
    FOR i IN REVERSE 1..Length(s) LOOP
        l := Substr(s, i, 1);

        -- here || are used for concatenation of string.
        t := t
             ||''
             ||l;
    END LOOP;

    IF t = s THEN
      dbms_output.Put_line(t
                           ||''
                           ||' is palindrome');
    ELSE
      dbms_output.Put_line(t
                           ||''
                           ||' is not palindrome');
    END IF;
END;

-- Program End

Output:

abccba is palindrome