An ORed search has the form "condition1" OR "condition2", as in this example:
WHERE column1 = 'x' OR column2 = 'y'
Here the optimizer's decision is to use a sequential scan.
The above warning does not apply if the same column is used in both conditions. For example:
WHERE column1 = 'x' OR column1 = 'y'
In such a case, the search is indexed because the expression is a range search. This subject will be revisited during the discussion of the IN predicate.
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