Question

我正在尝试创建一个包含5个表的视图但是在尝试将最后两个表连接在一起时遇到问题。

这是我当前的MySQL查询：

CREATE VIEW s_view AS
    SELECT AC.id, A.id AS account_id, A.name, A.description, A.industry, A.phone_fax, A.phone_office, A.shipping_address_street, A.shipping_address_city, A.shipping_address_state, A.shipping_address_postalcode, A.shipping_address_country, C.id AS contact_id, C.first_name, C.last_name, C.title, C.department, C.phone_home, C.phone_mobile, C.phone_work, C.primary_address_street, C.primary_address_city, C.primary_address_state, C.primary_address_postalcode, C.primary_address_country, EA.Email_address
    FROM ACCOUNTS A
    INNER JOIN ACCOUNTS_CONTACTS AS AC ON A.id = AC.account_id 
    INNER JOIN CONTACTS AS C ON C.id = AC.contact_id 
    INNER JOIN EMAIL_ADDR_BEAN_REL AS ER ON ER.bean_id = A.id
    INNER JOIN EMAIL_ADDRESSES AS EA ON ER.email_address_id = EA.id

我的表格按以下方式设置：

ACCOUNTS（id，first_name，last_name等）

联系人（身份证，姓名等）

ACCOUNT_CONTACTS（id，account_id，contact_id）

EMAIL_ADDR_BEAN_REL（id，bean_id（与account_id / contact_id相同），email_address_id）

EMAIL_ADDRESSES（email_address_id，email_address）

我遇到的问题是EMAIL_ADDR_BEAN_REL表有一个bean_id，可以引用account_id或contact_id。因此，当我加入表格时，它只返回帐户电子邮件地址，但我希望它返回帐户电子邮件地址和联系人电子邮件地址？

我有一种感觉，这是我加入桌面的方式的问题，但我不确定如何前进？

谢谢！

Answer 1

您可以为EMAIL_ADDR_BEAN_REL表设置2个单独的别名并适当引用它（因为您的结构必须添加另一个别名版本的email_address）：

CREATE VIEW s_view AS
    SELECT AC.id, A.id AS account_id, A.name, A.description, A.industry, 
        A.phone_fax, A.phone_office, A.shipping_address_street, 
        A.shipping_address_city, A.shipping_address_state, 
        A.shipping_address_postalcode, A.shipping_address_country, 
        C.id AS contact_id, C.first_name, C.last_name, C.title, 
        C.department, C.phone_home, C.phone_mobile, C.phone_work, 
        C.primary_address_street, C.primary_address_city, 
        C.primary_address_state, C.primary_address_postalcode, 
        C.primary_address_country, 
        EA.Email_address, 
        EA_C.Email_address AS Email_address_c
    FROM ACCOUNTS A
    INNER JOIN ACCOUNTS_CONTACTS AS AC ON A.id = AC.contact_id 
    INNER JOIN CONTACTS AS C ON C.id = AC.account_id 
    LEFT JOIN EMAIL_ADDR_BEAN_REL AS ER ON ER.bean_id = AC.id
        AND ER.bean_module = 'accounts'
    LEFT JOIN EMAIL_ADDR_BEAN_REL AS ER_C ON ER.bean_id = C.id
        AND ER_C.bean_module = 'contacts'
    LEFT JOIN EMAIL_ADDRESSES AS EA ON ER.email_address_id = EA.id
    LEFT JOIN EMAIL_ADDRESSES AS EA_C ON ER_C.email_address_id = EA_C.id

修改

由于您不一定有帐户或联系人的行（如果我从上面的评论中正确理解 - 谢谢，@ BK435），它现在被设置为LEFT JOIN。我还添加了bean_module列的指定（虽然我不确定您使用的是哪种代码）。

创建包含多个表的视图？

1 个答案:

修改