for example, the field addtime is a timestamp, and my business is almost always sorted inversely by the time of this field. Can I directly build such an index? You don"t need order by addtime desc?
for example, the field addtime is a timestamp, and my business is almost always sorted inversely by the time of this field. Can I directly build such an index? You don"t need order by addtime desc?
No, if you want the result set of sql to be ordered, you must specify the order by statement.
index is to find the
of the data more efficiently.sort belong to business requirements
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