如何比较两个查询? [英] How to compare two queries?

问题描述

我如何比较两个查询 X 和 Y 并说 X 比 Y 更好，因为它们在小案例场景中花费的时间几乎相同?

How can I compare two queries X and Y and say that X is better than Y, when they both take almost the same time in small cases scenarios?

问题是我有两个查询应该在一个非常大的数据库上运行，所以运行和评估不是一个很好的选择.因此，我们创建了一个小型数据库来执行一些测试.评估哪个查询更好是一个问题，因为在我们的测试基础上，它们几乎同时运行(大约 5 分钟).除了返回所需的时间，还有什么方法可以衡量查询的好坏?

The problem is that I have two queries that are supposed to run on a very big database, so run and evaluate is not quite an option. Therefore, we created a small database to perform some tests. Evaluating which query is better is a problem, since on our test base, they run in almost the same time (about 5 minutes). Besides the time taken to return, what is another way to measure how good a query is?

推荐答案

SET STATISTICS IO ON
SET STATISTICS TIME ON

运行查询并比较各种表的逻辑读取和执行时间.

Run the queries and compare logical reads for the various tables and execution times.

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