Abstraction is often defined similar to "hiding irrelevant details" so that one can focus on the forest instead of the trees. However, sometimes tree-level issu

Abstraction is often defined similar to "hiding irrelevant details" so that one can focus on the forest instead of the trees. However, sometimes tree-level issues affect the forest view also. An unexpectedly slow sort operation may be such a case. Normally you cay "ORDER BY x" in SQL and not worry about HOW the RDBMS sorts on "x": "How" is a "grunt-level detail" to you. But if the sort is slow or "wrong" (such as a collating sequence not expected by the customer), THEN you have to dig into the details, stepping out of the abstraction forest to visit and study individual trees.