Relational Algebra Check For Error

Hi could someone please verify my work. Im not sure if im doing any of this correctly and would greatly appreciate any help. I am not allow to use the Bow tie operator. Thank you.

Solution 1:

The professor told you how to do it:

You may use the expression LIKE "%James Stewart%" in your Relational Algebra.

It has been about a year since I have had to use relational algebra, but it will be whatever your pre-conditions are (this is a task for you) followed by the line:

LIKE %James Stewart%

The SQL statement would look something like this:

Select*from patrons p where Books.author LIKE%James Stewart%

You will find in your studies relational algebra does not deal with functions of SQL it just looks at the purely mathematical side of things.