如何解决 Mode.com 上的警告：“...”处或附近的语法错误？

Question

我是SQL的新手，通过Tina Huang老师了解到Mode.com，一个提供相当全面的SQL教程的网站。我遇到了这个问题，不知道如何解决，你们能帮帮我吗：

SELECT
  west, 
  midwest, 
  northeast,
  midwest + northeast AS "midwest_northeast_combined"
 FROM tutorial.us_housing_units
 Where west > "midwest_northeast_combined"

然后得到这样的警告：

Looks like something went wrong with your query.
org.postgresql.util.PSQLException: ERROR: syntax error at or near "midwest"
  Position: 1

Answer 1

"midwest_northeast_combined" 列对于 where 子句是未知的，因为在你的查询 midwest + northeast AS "midwest_northeast_combined" 在 where 子句之后计算，所以你必须在你的 where 子句中重复它:

SELECT
  west, 
  midwest, 
  northeast,
  midwest + northeast AS "midwest_northeast_combined"
 FROM tutorial.us_housing_units
 Where west > midwest + northeast

如何解决 Mode.com 上的警告：“...”处或附近的语法错误？

How to solve warning on Mode.com: syntax error at or near "..."?

sql

warnings