SQL选择要更新的列inside CASE条件 在SQL中,可以使用CASE语句来根据条件选择要更新的列。CASE语句是一种条件表达式,它允许根据不同的条件执行不同的操作。 在选择要更新的列时,可以使用CASE语句来根据条件选择不同的列进行更新。以下是一个示例: 代码语言:sql 复制 UPDATEtable_nameSETcolumn_name=C
问SQL选择要更新的列inside CASE条件EN语法格式 case "变量" in 值1) 指令1 ;; ...
CASE表达式 (1)CASE表达式可以让你可以在SQL中使用类似于if… then…else的逻辑而不需要调用程序 (2)一个简单的CASE表达式,Oracle将会搜索第一对when…then来与表达式做匹配,如果匹配了则返回表达式的值。如果没有任何一个when…then符合条件,将会执行 ELSE后面的语句,oracle将会返回else表...正则...
To finish up, let’s take a look at CASE functionality inside an UPDATE statement. The employees deserve a bonus in the form of extra vacation days. If you don’t have many left, you get 3 extra days. If you have between 10 and 20 hours left, you get 2 extra days, otherwise you ...
我正在尝试执行嵌套的 case 语句,当初始 case 语句中的条件未执行时,这些语句将被执行。我收到错误“无效的列名称 -
使用Count/group by in case 表达式问题描述 投票:0回答:2我试图显示该工作人员担任的所有工作职位(“代班老师”除外) - 如果该工作人员担任多个工作职位。并出示副课老师是否是老师(工作人员只持有副课老师一个职称)。 我使用了case表达式,然后在其中使用了Select语句,该语句使用了group by,以便统计该员工担任的...
Using CASE inside of aggregate functions In the previous examples, data was displayed vertically, but in some instances, you might want to show data horizontally. This is known as "pivoting" (like apivot tablein Excel). Let's take the following query: ...
Example: CASE in SQL Example: SQL CASE to Calculate the Discount Amount Let's take a look at another example where we want to provide a 10% discount on each order for a Christmas sale if the amount is 400 or more. SELECT order_id, customer_id, CASE WHEN amount >= 400 THEN (amoun...
SQL - Case: Real World ExampleAs a store owner, there might be a time when you would like to offer sale prices for products. This is a perfect opportunity to write a CASE query and alter the inventory sale prices at the presentation level rather than actually changing the price inside of...
如何将SELECT放入CASE中如果您只需要一个列表达式answer，则不需要函数或PL/pgSQL。这可以通过使用SQL中...