pg的列名是区分大小写的，但SQL语句会自动转换为小写，除非用双引号强调。

pg对大写字母的处理 列名要加双引号

添加一个 AA列

-- Column: "AA"

-- ALTER TABLE "version" DROP COLUMN "AA";

ALTER TABLE "version" ADD COLUMN "AA" character varying;
ALTER TABLE "version" ALTER COLUMN "AA" SET STORAGE EXTENDED;
ALTER TABLE "version" ALTER COLUMN "AA" SET DEFAULT 22;

错误的插入

insert into  version  (table_name,table_version,id,AA)values('cc','2',2,'3')
报错:
ERROR:  column "aa" of relation "version" does not exist
LINE 1: ...nsert into  version  (table_name,table_version,id,AA)values(...

将AA加引号

成功插入
insert into  version  (table_name,table_version,id,"AA")values('cc','2',2,'3')
查询成功: 共计 1 行受到影响，耗时: 15 毫秒(ms)。

查询

select  * from  version  where AA='3'
报错：
ERROR:  column "aa" does not exist
LINE 1: select  * from  version  where AA='3'

将AA加引号

这样才 可以 查询出

exchange=# select  * from  version  where "AA"='3';
 table_name | table_version | id | rownum | AA 
------------+---------------+----+--------+----
 cc         |             2 |  2 |     18 | 3
 cc         |             2 |  2 |     19 | 3
(2 rows)

exchange=#