掌握CASE 语句使我们能够直接在 SQL 查询中执行复杂的条件逻辑。无论对数据进行分类、对结果进行优先级排序,还是进行过滤,CASE 语句都是一个宝贵工具。通过了解其语法并探索实际示例,可以在数据库操作中充分利用 SQL CASE 语句的潜力。
在SQL Server中,SELECT语句用于从数据库中检索数据。CASE语句是SELECT语句中的一种条件表达式,用于根据条件返回不同的结果。 CASE语句有两种形式:简单CASE表达式和搜索CA...
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possible. Aggregate expressions that appear in WHEN arguments to aCASEexpression are evaluated first, then provided to theCASEexpression. For example, the following query produces a divide by zero error when producing the value of the MAX aggregate. This occurs prior to evaluating theCASEexpression....
Azure SQL 托管实例 适用于:Azure SQL 数据库 和 SQL Server(从 SQL Server 2017 (14.x) 开始) 本机编译的 T-SQL 模块支持 CASE 表达式。 下面的示例演示了在查询中使用 CASE 表达式的方法。 -- Query using a CASE expression in a natively compiled stored procedure...
Hello, when running the following example query: select top 1 * from user_db.dbo.USER_TABLE We get: Invalid object name 'user_db.dbo.USER_TABLE' But when we run it all lower case as: select top 1 * from user_db.dbo.user_table It succeeds returning the…
In theReport Datapane, right-click the name of the data source that you added to the report, and then clickAdd Dataset. In theDataset Propertiesdialog box, clickQueryin the list on the left, type the following SQL query in theQuerybox, and then clickOK: ...
Assume that you execute a Transact-SQL query in Microsoft SQL Server 2012. When the query contains a long case statement, the query fails. Additionally, you receive the following error: Msg 8631, Level 17, State 1, Line 7...
Assume that you execute a Transact-SQL query in Microsoft SQL Server 2012. When the query contains a long case statement, the query fails. Additionally, you receive the following error: Msg 8631, Level 17, State 1, Line 7...
Then we launch the spark application using the spark parameters discussed in the Spark SQL Configuration section. In all our performance runs, the queries are executed in sequence 1 to 99. Once the run is complete, we collect the query time results from...