We can have multiple conditions in a Case statement; however, it works in a sequential model. If one condition is satisfied, it stops checking further conditions We cannot use a Case statement for checking NULL values in a table Conclusion The Case statement in SQL provides flexibility in ...
CASE 语句也是用来进行条件判断的,它提供了多个条件进行选择,可以实现比 IF 语句更复杂的条件判断。CASE 语句的基本形式如下: CASE case_value WHEN when_value THEN statement_list [WHEN when_value THEN statement_list]... [ELSE statement_list] END CASE 情况1:类似于java中的switch语句,一般用于实现的等值...
SQL 条件语句 (IF, CASE WHEN, IFNULL) 1、IF 1.1 表达式: IF( expr1 , expr2 , expr3 ) expr1条件,条件为true,则值是expr2 ,false,值就是expr3 示例; SELECT o.id,u.account,catagory
Once the condition is met, the CASE statement will stop verifying further and it will return the result.If none of the conditions are met (TRUE), then it returns the value mentioned in the ELSE clause. It returns NULL if the ELSE part is not mentioned and none of the conditions are ...
SQL: CASE Statement 1.CASE 写法如下: CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 WHEN conditionN THEN resultN ELSE result END; 解释:1)先匹配第一条,不匹配的话继续第二条,如此循环,
SELECT contact_id, CASE WHEN website_id = 1 THEN 'TechOnTheNet.com' WHEN website_id = 2 THEN 'CheckYourMath.com' END With the ELSE clause omitted, if no condition was found to be true, the CASE statement would return NULL.
SQL CASE The SQLCASEstatement evaluates a list of conditions and adds a column with values based on the condition. For example, -- add a new column 'order_volume' in the Orders table-- and flag any order greater than 10000 as 'Large Order'-- and smaller than 10000 as 'Small Order'...
CASE WHEN is like an IF statement in a programming language. It is useful when we need to calculate a statistic on a certain subset of the data. In the image above, I calculate an average price for products sold in the US. I wasn’t careful with the ELSE in the CASE WHEN. ...
[BusinessEntityID],[JobTitle],[BirthDate],[SalariedFlag],IsEmployee=CASE [SalariedFlag] WHEN 1 THEN'Salaried Employee'WHEN 0 THEN'Contractor'ELSE'N/A'END FROM [HumanResources].[Employee] The downside of the simple CASE statement is that you can only check for equality. ...
Updating Multiple Rows without using CASE WHEN in MySQL This UPDATE Statement in SQL allows us to update multiple rows at once by applying the same value to all the matching records. Syntax: UPDATE table_name SET column_name = new_value WHERE columnname IN (value1...); Example: -- To ...