The chapters to pay close attention to are 5 and 6.
Query Languages and the Relational Algebra
This covers the definition of the terms and provides examples of the result sets. Very useful and in my case filled in gaps in my knowledge. It is set theory algebra based but I have a college math background so that was not a problem for me. I don't think he obfuscates any of the explanations so you shouldn't have any problems understanding it.
ACCESS Structured Query Language (SQL)
In this chapter Mr.. Roman covers the SQL language implemented in ACCESS. He continues to give examples of the different forms of joins covered in Chapter 5.
These two chapters were very instrumental in my getting my ACCESS record sets built and executed in a minimum of time and correctly. I found that, after a month's lack of use, I had to refresh myself but the refresh effort was considerably less than grasping it the first time.
So, good luck. I hope this helps you.
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