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使用条件/if-else/case生成列以填充新列mysql_Mysql_Sql_If Statement_Conditional Statements_Generated Columns - Fatal编程技术网

使用条件/if-else/case生成列以填充新列mysql

使用条件/if-else/case生成列以填充新列mysql,mysql,sql,if-statement,conditional-statements,generated-columns,Mysql,Sql,If Statement,Conditional Statements,Generated Columns,我有一个专栏城市,我想创建一个新的专栏-地铁,我想让它检查 如果城市位于('x'、'y'、'z'),则Metro='Metro'或'Non Metro' 我还有另外一组值要放在这个案例中,但我猜如果我做到了这一点,也会成功。我希望它存储到表中,而不是select查询您需要修复大小写表达式,基本上: ALTER TABLE sales ADD COLUMN Metro_city VARCHAR(45) GENERATED ALWAYS AS (case when CITY in ('M

我有一个专栏城市,我想创建一个新的专栏-地铁,我想让它检查 如果城市位于('x'、'y'、'z'),则Metro='Metro'或'Non Metro'


我还有另外一组值要放在这个案例中,但我猜如果我做到了这一点,也会成功。我希望它存储到表中,而不是select查询

您需要修复
大小写
表达式,基本上:

ALTER TABLE sales ADD COLUMN Metro_city VARCHAR(45) GENERATED ALWAYS AS
      (case when CITY in ('Mumbai ', 'Delhi' , 'Bangalore')
            then 'Metro'
            else 'Non-Metro'
       end ) STORED;
ALTER TABLE sales ADD COLUMN Metro_city VARCHAR(45) GENERATED ALWAYS AS
      (case when CITY in ('Mumbai ', 'Delhi' , 'Bangalore')
            then 'Metro'
            else 'Non-Metro'
       end ) STORED;