• Exploration of in function of slice in go


    Before I saw a question in Zhihu: why doesn’t golang have the same function as in Python? As a result, I searched the problem and found that many people still have such questions. Let’s talk about this topic today. In is a very common function, which may also be called contains in some languages. Although […]

  • Solution to the problem that not in is null in MySQL


    Some time ago, when I was doing a small function in the company, I counted the number of data in a certain situation and then modified the problem. At that time, I thought it was very simple. I wrote the following SQL: SELECT COUNT(*) FROM t1 where tl.c1 not IN (SELECT t2.c1 FROM t2); The […]

  • Differences between @Service and @Resource annotations in Spring


    Differences between @Service and @Resource annotations in Spring 1 Preface When we use spring framework, annotations are an “indispensable” part. She helps us get rid of the tedious task of configuring XML files, but one thing we need to grasp is “3He”, that is, “When, Where and Where to Annotate?” In this blog post, the […]

  • The Usage of RAISERROR in SQL Server


    Use of RAISERROR in SQL Server The role of raiserror: raiserror is used to throw an error。 [The following information comes from the help of SQL Server 2005] Its grammar is as follows: RAISERROR ( { msg_id | msg_str | @local_variable } { ,severity ,state } [ ,argument [ ,…n ] ] ) [ WITH […]