String Operations

1. The most commonly used operation on strings is pattern matching using the operator like.
2. String matching operators % (any substring) and _ (underscore, matching any character).

   E.g., ``___%'' matches any string with at least 3 characters.

3. Patterns are case sensitive, e.g., ``Jim" does not match ``jim".
4. Use the keyword escape to define the escape character.

   E.g., like ``ab%tely % '' escape `` '' matches all the strings beginning with ``ab'' followed by a sequence of characters and then ``tely'' and then ``% ''.

   Backslash overrides the special meaning of these symbols.

5. We can use not like for string mismatching.
6. Example. Find all customers whose street includes the substring ``Main''.

    select cname
   
   		 from customer
   
   		 where street like ``%Main%''
   
   

7. SQL also permits a variety of functions on character strings, such as concatenating (using `` ''), extracting substrings, finding the length of strings, converting between upper case and lower case, and so on.