CASE WHEN 语句可以嵌套使用,以处理更复杂的条件逻辑。嵌套 CASE WHEN 的语法如下: sql SELECT column1, CASE WHEN condition1 THEN CASE WHEN nested_condition1 THEN nested_result1 WHEN nested_condition2 THEN nested_result2 ELSE nested_default_result END WHEN condition2 THEN result2 ELSE default_result...
https://linuxhint.com/sql-case-statement/ This tutorial mainly focuses on building a nested case statement in conjunction with the WHEN clauses. Nested CASE WHEN Statements In SQL, we can use a set of nested CASE WHEN statements in SQL to evaluate the multiple conditions and return a differe...
ng-form and ng-submit in a ng-repeat I have been trying to get a nested form to validate properly and then call a function on my controller when the submit button is clicked. I have tried remove all buttons except the submit button and i......
这种用法是根据列的值来判断条件,并返回对应的结果。 搜索CASE WHEN语句: CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 ... ELSE result END 复制代码 这种用法是根据条件进行判断,并返回对应的结果。 嵌套CASE WHEN语句: CASE WHEN condition1 THEN CASE WHEN nested_condition1 THEN nest...
搜索CASE WHEN语句: CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 ... ELSE result END 复制代码 根据条件进行匹配,如果满足condition1,则返回result1;如果满足condition2,则返回result2;否则返回result。 嵌套CASE WHEN语句: CASE WHEN condition1 THEN CASE WHEN nested_condition1 THEN nes...
`CASE WHEN` 后面可以跟多个 `WHEN` 条件,最后的 `ELSE` 是可选的,用于处理未匹配到任何条件时的默认情况。 另外,`CASE WHEN` 也可以嵌套使用,用于处理更复杂的条件判断。例如: ```sql SELECT column1, column2, CASE WHEN condition1 THEN CASE WHEN nested_condition1 THEN result1 WHEN nested_condition...
selectcount(casewhen rn=1then task_idelsenullend)task_numfrom(select task_id,row_number()over(partition by task_id order by start_time)rn from Task)tmp; 此外,再借助一个表 test 来理理 distinct 和 group by 在去重中的使用: 代码语言:javascript ...
嵌套CASE语句可以在WHEN或ELSE后面再嵌套一个CASE语句,用于处理更复杂的条件逻辑。例如: 代码语言:txt 复制 CASE WHEN condition1 THEN CASE WHEN nested_condition1 THEN nested_result1 WHEN nested_condition2 THEN nested_result2 ... ELSE nested_resultN END WHEN condition2 THEN result2 ... ELSE resultN...
WHEN'MD'THEN'Maryland' WHEN'UT'THEN'Utah' ENDASStateName FROMpubs.dbo.authors ORDERBYau_lname DECODE is considered the most powerful function in Oracle. Oracle 8i release introduced the CASE expression. The CASE expression can do all that DECODE does plus lot of other things including IF-THEN...
There are times where you need to write a single TSQL statement that is able to return different TSQL expressions based on the evaluation of another expression. When you need this kind of functionality you can use the CASE expression or IIF function to meet this requirement. In this article ...