Books by C. J. Date

Anyone familiar with the following books by C. J. Date:

• SQL and Relational Theory
• Database Design and Relational Theory
• Relational Theory for Computer Professionals

How do they compare? I want to know for the purpose of deciding which to invest time and money into.

Database Design and Relational Theory published by APress I think is the most economical. Is it a good investment of time?

I have been programming for half a century. I am asking as a programmer. I am interested in read a book from a recognized authority such as C. J. Date.

Normally I would first try to search for answers prior to posting but the name Date is likely to return many false positives.