Mr. Pinal Dave (a MS SQL master) had an interesting post today on his blog.
The question was if it is possible to see if a string is a palindrome or not. This question was asked to him from a friend who wanted to know because he was building captcha and they may display the image mirrored and if the word was a palindrome, one could not know if it was mirrored or not.
When reading his post I thought if this was possible in mySQL and it is.
The mySQL verison is very similar to the T-SQL variant
Note that we use REPLACE to remove all spaces from the @PalinString variable.
[precode]
SET @PalinString = ‘Was it a car or a cat I saw’;
SELECT CASE WHEN
REPLACE(@PalinString, ‘ ‘, ”) = REVERSE(REPLACE(@PalinString, ‘ ‘, ”)) THEN ‘Palindrome’
ELSE ‘Not Palindrome’ END AS Answer
[/precode]
This will retunr the Answer “Palindrome” if @PalinString is or “Not Palindrome” if its not.
I am sure that there are many more situations where this can be applied.