PostgreSQL-错误：列XXX不存在

Question

我对PostgreSQL完全不熟悉。我有一个包含下一列的表格：

db_1=# select * from table1 where false;  
 id | createdat | description | index | name | updatedat | type_id |dtype 
----+-----------+-------------+-------+------+-----------+---------+-----  
(0 rows)  

内容如下：

db_1=# select id,name,dtype from table1;  
id |  name   |  dtype  
---+---------+--------------  
1  |  name1  | PlantControl  
2  |  name2  | PlantSystem  
3  |  name3  | PlantControl  
4  |  name4  | PlantControl  
5  |  name5  | PlantSystem  
6  |  name6  | AlarmSystem  
7  |  name7  | AlarmSystem  
(7rows)  

如果我尝试使用dtype=PlantSystem删除每一行，则会出现下一个错误：

db_1=# delete from table1 where dtype=PlantControl;  
ERROR:  column "plantcontrol" does not exist  
LINE 1: delete from table1 where dtype=PlantControl;

显然，PlantControl不是列，列是dtype ...

Answer 1

您需要引用PlantControl值。

delete from table1 where dtype='PlantControl';