NULL 值作为一种特殊的存在，无论它出现在哪种运算中，都可能导致意料之外的结果。因此在数据处理之前，我们通常需要对 NULL 值进行筛选和处理，以避免出现潜在的问题。 在SQL优化中，谨慎操作NULL值至关重要。NULL值作为特殊的标记，表示数据缺失或未知 ...

NULL in SQL is a powerful concept, representing the absence of a value. It’s used when data is unavailable or unknown, but its usage requires careful consideration. The first step is understanding the ...

SQL Server Management Studio or SSMS allows you to connect to the SQL server and execute queries. In this tutorial, we will see how you can install and configure SQL Server Management Studio in ...

在实时数据开发过程中，大家经常会用 Flink SQL 或者 Flink DataStream API 来做数据加工。通常情况下选用2者都能加工出想要的数据，但是总会有 Flink SQL 覆盖不了的问题，但 SQL 的易用性又难以让人释怀。所以有些场景在使用 FLink SQL 开始就与需要额外注意，下面就 ...

Abstract: The lack of information within relational databases expressed as NULL values presents a problem in ensuring the quality of data and the information retrieved by SQL queries. This is so ...

Part of the SQL Server 2022 blog series. Time series data is a set of values organized in the order in which they occur and arrive for processing. Unlike transactional data in SQL Server, which is not ...

SQL (Structured Query Language) has been with us for more than half a century and it’s not going away anytime soon. Popular in both traditional relational databases and newer NoSQL databases ...