sql语句错误:"列..不存在"

Question

我试着从postgres控制台这个命令:

select sim.id as idsim, 
       num.id as idnum 
from main_sim sim 
  left join main_number num on (FK_Numbers_id=num.id);

我得到了这样的答复:

ERROR:  column "fk_numbers_id" does not exist
LINE 1: ...m from main_sim sim left join main_number num on (FK_Numbers...

但如果我只是检查我的表:

dbMobile=# \d main_sim

 id              | integer               | not null default

 Iccid           | character varying(19) | not null

...

 FK_Device_id    | integer               | 

 FK_Numbers_id   | integer               | 

Indexes:
    "main_sim_pkey" PRIMARY KEY, btree (id)
    "main_sim_FK_Numbers_id_key" UNIQUE, btree ("FK_Numbers_id")
    "main_sim_Iccid_key" UNIQUE, btree ("Iccid")
    "main_sim_FK_Device_id" btree ("FK_Device_id")
Foreign-key constraints:
    "FK_Device_id_refs_id_480a73d1" FOREIGN KEY ("FK_Device_id") REFERENCES main_device(id) DEFERRABLE INITIALLY DEFERRED
    "FK_Numbers_id_refs_id_380cb036" FOREIGN KEY ("FK_Numbers_id") REFERENCES main_number(id) DEFERRABLE INITIALLY DEFERRED

......因为我们可以看到该列存在.

可能是语法错误,但我无法看到...

任何帮助将不胜感激.阿莱西奥

Answer 1

不,该列FK_Numbers_id不存在,只"FK_Numbers_id"存在一列

显然,您使用双引号创建了表,因此所有列名称现在都区分大小写,您必须始终使用双引号:

select sim.id as idsim, 
       num.id as idnum 
from main_sim sim 
   left join main_number num on ("FK_Numbers_id" = num.id);

要概述手册中已经记录的内容:

列foo和FOO是相同的,所述列"foo"和"FOO"都没有.