Next, ensure that the index has these columns in the proper sequence (according to the ORDER BY clause), so that a sort can be avoided.
接下来,确保索引中这些列有适当的顺序(按照ORDER by子句),这样可以避免排序。
Note that an order by clause in the SELECT statement would not have any effect on the order of the array elements, as it would apply to the rows returned by the statement.
请注意,select语句中的ORDER BY子句不会对阵列元素的顺序产生任何影响,因为它将应用于该语句返回的行。
TOTAL_SORT_TIME: the total elapsed time (in milliseconds) for all sorts that have been executed by the statement (e.g. query statement using ORDER by clause).
TOTAL_SORT _ TIME:该语句已经执行的所有排序的总消耗时间(微秒级)(例如,使用ORDER BY子句的查询语句)。
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