Question at position 46 Joining conditions for an INNER JOIN always need to use '='.TrueFalse

Question

BlackTom AI · Accepted Answer

Reframing the question helps examine what INNER JOIN conditions can look like. 
Option 1: 'True' claims that joining conditions for an INNER JOIN must always use =. This is not accurate, because SQL allows a variety of boolean expressions in the ON clause, not limited to equality. For example, you can join on inequalities, ranges, or other predicates expressed between columns from the two tables. 
Option 2: 'False' states that the requirement is not always '='. This is correct: the ON condition can be any valid boolean expression that relates columns from the two tables involved in the join. Examples include ON a.col1 > b.col2, ON a.col3 BETWEEN b.col4 - 10 AND b.col4 + 5, ON a.col5 IS NOT NULL AND b.col6 IS NOT NULL, or ON a.col7 = b.col7 AND a.col8 <> b.col8. 
To see why the first option is misleading, consider that the join predicate is the overall filter that determines which row combinations are paired; equality is a common pattern (natural joins and equijoins), but it is not a syntactic requirement of the JOIN syntax itself. The database engine accepts any valid boolean expression in the ON clause, as long as it returns true for the pairs you intend to match. 
In short, the claim that '=' is always required is incorrect because the ON clause supports a broader set of conditions beyond simple equality. The statement in Option 2 correctly reflects this fact by marking the assertion as False.

Question at position 46 Joining conditions for an INNER JOIN always need to use '='.TrueFalse

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