-- multiple CASE conditions in SQLSELECTcustomer_id, first_name,CASEWHENcountry ='USA'THEN'United States of America'WHENcountry ='UK'THEN'United Kingdom'ENDAScountry_nameFROMCustomers; Run Code Here, the result
那么你应该首先做一个使用分析变量的子查询:sum() over (),它将显示每个字段的聚合数据,然后你可以...
<result> is an arbitrary SQL expression: it can be a simple expression like a constant or column name, or also a complex SQL expression containing subqueries and, of course, nested case expressions. A case expression can contain several when-then pairs. This allows for multiple conditions even...
case WHEN cast(`status` AS SIGNED) < 45 THEN '1' WHEN cast(`status` AS SIGNED) > 44 AND...
With the searched CASE expression, we can have multiple WHEN conditions: SELECT [BusinessEntityID],[JobTitle],[HireDate],Seniority=CASE WHENDATEDIFF(YEAR,[HireDate],GETDATE())>10 THEN'Longer than 10 years'WHENDATEDIFF(YEAR,[HireDate],GETDATE())=10 THEN'Exactly 10 years'WHENDATEDIFF(YEAR,[...
在case表达式sql中检查多个条件你可以使用string_split为了达到这个目的。
The output fromEXPLAINshowsALLin thetypecolumn when MySQL uses afull table scanto resolve a query. 慢SQL 分析与优化 https://mp.weixin.qq.com/s/CaSVhAJgycjjbCxAkII2ZA 从系统设计角度看,一个系统从设计搭建到数据逐步增长,SQL 执行效率可能会出现劣化,为继续支撑业务发展,我们需要对慢 SQL 进行分析和...
Evaluates a list of conditions and returns one of multiple possible result expressions. TheCASEexpression has two formats: The simpleCASEexpression compares an expression to a set of simple expressions to determine the result. The searchedCASEexpression evaluates a set of Boolean expressions to determin...
Evaluates a list of conditions and returns one of multiple possible result expressions. TheCASEexpression has two formats: The simpleCASEexpression compares an expression to a set of simple expressions to determine the result. The searchedCASEexpression evaluates a set of Boolean expressions to determin...
between network interfaces,security groups,and virtual machines.Considering the complexity,the verbose query might be the best approachformaintainability and debugging purposes.Compact queries can be harder to debug and understand,especially when dealingwithnestedJSONBstructures and multipleJOINconditions. ...