SELECTCustomers.CustomerName,Orders.OrderIDINTOCustomersOrderBackup2017FROMCustomersLEFTJOINOrdersONCustomers.CustomerID=Orders.CustomerID; 提示:SELECT INTO还可以用于使用另一个表的架构创建新的空表。只需添加一个导致查询不返回数据的WHERE子句: 代码语言:sql AI代码解释 SELECT*INTOnewtableFROMoldtableWHERE1=0;...
这里如果用sql来查询的话,使用case when就很简单明了。 代码语言:javascript 代码运行次数:0 SELECT*,CASEWHENchinese_score>=90AND math_score>=90THEN'A'WHENchinese_score>=80AND math_score>=80THEN'B'ELSE'C'ENDASscore_typeFROMscores 如果用pandas apply方法来实现的话,需要自定义一个判断函数,用来对成...
SELECT*INTOCustomersBackup2017 FROMCustomers; 以下SQL 语句使用IN子句将表复制到另一个数据库中的新表中: SELECT*INTOCustomersBackup2017IN'Backup.mdb' FROMCustomers; 以下SQL 语句仅复制一些列到新表中: SELECTCustomerName, ContactNameINTOCustomersBackup2017 FROMCustomers; 以下SQL 语句仅将德国客户复制到新表中...
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'SELECT*,CASE...
要求:创建表,源表,表名: Stu , 只用一句sql 得到转换结果。 解答: 方法一 :通过生成临时表的方式操作 select name ,sum(yw) as '语文',sum(sx) as '数学',sum(wy) as '英语' from( select name , CASE subject WHEN '语文' THEN score END AS yw, ...
The case statement in SQL returns a value on a specified condition. We can use a Case statement in select queries along with Where, Order By, and Group By clause. It can be used in the Insert statement as well. In this article, we would explore the CASE statement and its various use...
SQL SELECT INTO 语句 语句将数据从一个表复制到一个新表中。 SELECT INTO 语法 将所有列复制到新表中: 只复制一些列到新表中: 新表将按照在旧表中定义的列名和类型创建。您可以使用子句创建新的列名。 SQL SELECT INTO 示例 以下SQL 语句创建的备份副本: ...
SQL SELECT INTO 示例 以下SQL 语句创建Customers的备份副本: SELECT*INTOCustomersBackup2017FROMCustomers; 1. 2. 以下SQL 语句使用IN子句将表复制到另一个数据库中的新表中: SELECT*INTOCustomersBackup2017IN'Backup.mdb'FROMCustomers; 1. 2. 以下SQL 语句仅复制一些列到新表中: ...
以下SQL 语句创建Customers的备份副本: SELECT*INTOCustomersBackup2017FROMCustomers; 以下SQL 语句使用IN子句将表复制到另一个数据库中的新表中: SELECT*INTOCustomersBackup2017IN'Backup.mdb'FROMCustomers; 以下SQL 语句仅复制一些列到新表中: SELECTCustomerName, ContactNameINTOCustomersBackup2017FROMCustomers; ...
Let’s illustrate with an example. The following SQL statement will return “Monday” if today is a Monday, otherwise it returns “Not a Monday”. SETDATEFIRST1-- first day of the week is a MondaySELECTCASEWHENDATEPART(WEEKDAY,GETDATE())=1THEN'Monday'ELSE'Not a Monday'END ...