I'm sceptical of that article, it's making guesses about the limitations of SQL query optimisers.
Consider the Simple example it presents. The article is in effect implying that no query optimiser would be able to figure out the equivalence of the two predicates.
(Let's ignore that the two predicates aren't actually equivalent; the first version may raise an exception if myIntColumn is negative, depending on the DBMS.)
I should have been clearer, I meant the Wikipedia article.
Ozar's article is much better. It doesn't make sweeping assumptions about the limitations of all query optimisers, or basic oversights in contrasting supposedly equivalent predicates.
Consider the Simple example it presents. The article is in effect implying that no query optimiser would be able to figure out the equivalence of the two predicates.
(Let's ignore that the two predicates aren't actually equivalent; the first version may raise an exception if myIntColumn is negative, depending on the DBMS.)