简短的回答是 - 否长答案是 - 绝对不会

The short answer is - no The long answer is - absolutely not

它是否优化了 LIKE('%%') 查询，因为它意味着没有什么可比较的?

Does it optimize LIKE('%%') query since it means there is nothing to compare?

该陈述不真实，因为有可以比较的东西.以下是等价的

The statement is untrue, because there is something to compare. The following are equivalent

WHERE column LIKE '%%'
WHERE column IS NOT NULL

IS NOT NULL 需要进行表扫描，除非该列中的非空值很少并且索引良好.

IS NOT NULL requires a table scan, unless there are very few non-null values in the column and it is well indexed.

有关 SQL Server 中动态搜索过程的资源:
您只需必须阅读 SQL Server MVP Erland Sommarskog 的这篇文章http://www.sommarskog.se/dyn-search.html(选择您的版本，或同时阅读)

Resource on Dynamic Search procedures in SQL Server:
You simply must read this article by Erland Sommarskog, SQL Server MVP http://www.sommarskog.se/dyn-search.html (pick your version, or read both)

否则，如果您需要 CONTAINS 样式搜索的良好性能，请考虑使用 SQL Server 全文引擎.

Otherwise if you need good performance on CONTAINS style searches, consider using SQL Server Fulltext engine.