sql - postgres dblink转义单引号

Question

相关链接:

• String literals and escape characters in postgresql

这是我的错误:

ERROR:  type "e" does not exist

这是我的查询:

SELECT *
FROM dblink('host=theHostName port=1234 dbname=theDBName user=theUser password=thePassword',
    E'SELECT field_1, 
    CASE WHEN field_2 IS NOT NULL 
    THEN \'inactive\' ELSE \'active\' 
    END AS field_status 
    FROM the_table 
     ') 
AS linkresults(field_1 varchar(20),field_2 varchar(8))

如果我使用双引号，删除单引号的反斜杠转义并删除 SELECT 语句前的 E

SELECT *
FROM dblink('host=theHostName port=1234 dbname=theDBName user=theUser password=thePassword',
    "SELECT field_1, 
    CASE WHEN field_2 IS NOT NULL 
    THEN 'inactive' ELSE 'active' 
    END AS field_status 
    FROM the_table 
     ") 
AS linkresults(field_1 varchar(20),field_2 varchar(8))

我明白了:

NOTICE:  identifier "SELECT ..." will be truncated

而且由于我的查询已被截断，我也得到了错误。

我以前用dblink逃过，有没有服务器设置或者我需要配置的东西？

我知道如果我在 sql server 本身上运行该查询，但使用 dblink 则不行。有什么想法吗？

Postgres 版本 8.4

Answer 1

尝试将 \'inactive\' 替换为 ''inactive'' -- 注意:两个单引号

   SELECT *
    FROM dblink('host=theHostName port=1234 dbname=theDBName user=theUser password=thePassword',
        'SELECT field_1, 
        CASE WHEN field_2 IS NOT NULL 
        THEN ''inactive'' ELSE ''active'' 
        END AS field_status 
        FROM the_table 
         ') 

AS linkresults(field_1 varchar(20),field_2 varchar(8))

替代(先前)解决方案

   SELECT *
    FROM dblink('host=theHostName port=1234 dbname=theDBName user=theUser password=thePassword',
        'SELECT field_1, 
        CASE WHEN field_2 IS NOT NULL 
        THEN E\'inactive\' ELSE E\'active\' 
        END AS field_status 
        FROM the_table 
         ') 

AS linkresults(field_1 varchar(20),field_2 varchar(8))