LOWER and UPPER
The functions LOWER and UPPER allow the case of a string to be altered quickly and easily, so that all the characters are lower- or uppercase, respectively. These functions are supported in all the database implementations covered in this book.
SELECT LOWER('You Talkin To ME?'), UPPER('you talking to me?!'); -> you talking to me?, YOU TALKIN TO ME?!
The various database vendors also support a variety of other text formatting functions that are specific to their implementation.