列引用对于函数中的局部变量不明确

Question

以下是我的函数

CREATE OR REPLACE FUNCTION  add_config_to_enterprise(configKey character varying, enterpriseValue character varying) RETURNS void AS 
$BODY$
DECLARE
entId character varying;
   BEGIN
        FOR entId IN
    SELECT enterprise_id
    FROM tenant
LOOP
    INSERT INTO enterprise_configuration(enterprise_configuration_id, product_configuration_id, enterprise_id, value)
SELECT *
FROM 
    (SELECT uuid_generate_v4(),
        (SELECT pc.product_configuration_id
        FROM product_configuration pc
        WHERE pc.configuration_key = configKey), 
            entId, enterpriseValue) AS tmp
            WHERE NOT EXISTS 
            (SELECT e.enterprise_configuration_id
            FROM enterprise_configuration e
            WHERE e.enterprise_id = entId AND e.product_configuration_id = 
                (SELECT p.product_configuration_id
                FROM product_configuration p
                WHERE p.configuration_key = configKey));

END LOOP;


   END;

$BODY$ LANGUAGE 'plpgsql'

但是在调用这个函数时出现以下错误

ERROR:  column reference "entid" is ambiguous
LINE 12:             WHERE e.enterprise_id = entId AND e.product_conf...
                                             ^
DETAIL:  It could refer to either a PL/pgSQL variable or a table column.

任何 table 中都不存在名为 entid 的列。为什么会报这样的错误？

Answer 1

在WHERE条件中使用子查询别名：

...
SELECT *
FROM 
    (SELECT uuid_generate_v4(),
        (SELECT pc.product_configuration_id
        FROM product_configuration pc
        WHERE pc.configuration_key = configKey), 
            entId, enterpriseValue) AS tmp
            WHERE NOT EXISTS 
            (SELECT e.enterprise_configuration_id
            FROM enterprise_configuration e
            WHERE e.enterprise_id = tmp.entId AND e.product_configuration_id = -- here
                (SELECT p.product_configuration_id
                FROM product_configuration p
                WHERE p.configuration_key = configKey));
...

或在子查询的SELECT列表中重命名entId：

...
SELECT *
FROM 
    (SELECT uuid_generate_v4(),
        (SELECT pc.product_configuration_id
        FROM product_configuration pc
        WHERE pc.configuration_key = configKey), 
            entId as eId, enterpriseValue) AS tmp -- here
            WHERE NOT EXISTS 
            (SELECT e.enterprise_configuration_id
            FROM enterprise_configuration e
            WHERE e.enterprise_id = entId AND e.product_configuration_id =
                (SELECT p.product_configuration_id
                FROM product_configuration p
                WHERE p.configuration_key = configKey));
...

Answer 2

问题是您在查询中定义的别名 tmp 的子查询有一个名为 entid 的列，因此解析器不知道是否引用了 entid在 WHERE 条件中引用该列或函数变量。

确实，它们包含相同的值，所以在现实中没有关系，但仍然存在句法歧义。

您必须使用别名 tmp 或函数名称 add_config_to_enterprise 来限定 WHERE 条件中的 entid 以解决歧义.

您的查询不必要地复杂且缩进错误，以至于我无法理解和改进它。简化它可以解决这个问题。

列引用对于函数中的局部变量不明确

Column reference is ambiguous for local variable in function

sql

postgresql

plpgsql