How to write sql query to get data which the best matches with data in database

Question

I work on AI chat bot. I need sql query to select a single row from database where user input and text in database best matches. (also match percentage > %80)

For Example: "Hello" and "Hello!" , "Hi how are you" and "how are you?", "What is your name?" and "Wat is your name?"

My purpose is to get answer in case of clerical errors. Thanks in advance and sorry for my english

Bot LINK: http://developersland.net/chatbot/jessica.html

Answer 1

Search a levenstein distance algoritm implementation on google (like this) and then

select text 
from mytable 
where levenshtein_ratio(text, 'text_to_compare') > 80 
limit 1