检索从表中的数据，其中一个具有多个列指向在其它相同的主键？

Question

我不负责这个设计，但我必须从这种模式，它看起来是这样的（SQL Server 2000中）提取数据：

CREATE TABLE contract 
(
    contract_id int, 
    account_id int,    /* account table */ 
    responsible_id int,   /* account table */ 
    holding_id int,    /* account table */ 
    billingaddress_id int,  /* address table */ 
    deliveryaddress_id int,  /* address table */ 
) 

CREATE TABLE address 
(
    address_id int, 
    postalcode char(4), 
) 

CREATE TABLE account 
(
    account_id int, 
    firstname varchar(40), 
    billingaddress_id int,  /* address table */ 
    deliveryaddress_id int,  /* address table */ 
) 

的ACCOUNT_ID，responsible_id和holding_id在合约表可以为空，共享值或具有不同的值。它可能有也可能没有账单和/或送货地址。 一个帐户实体总是有一个计费或送货地址，都可以是相同的。

我必须找到与合同有关的所有帐户（即合同具有相同的帐户，负责人或持有ID作为帐户ID），并与具有特定邮政编码的地址（直接或通过合同）。

的问题似乎是2倍：
一）检索）从过滤的结果与合同 B关联账户（一），以获得具有一定邮政编码

这不起作用关联账户因为如果ACCOUNT_ID不与有问题的邮政编码相关，但holding_id，那么它不会返回：

FROM account 
INNER JOIN contract 
    ON account.account_id = 
     CASE WHEN NOT IsNull(contract.account_id) THEN contract.account_id 
     WHEN NOT IsNull(contract.responsible_id) THEN contract.responsible_id 
     ELSE contract.holding_id END 

这是迄今为止因某种原因太慢（FK的未索引 - 等待30分钟，它未返回）：

FROM account 
INNER JOIN contract 
    ON account.account_id = contract.account_id 
    OR account.account_id = contract.responsible_id 
    OR account.account_id = contract.holding_id 

似乎已经工作的唯一的事情是一个联盟，但我仍然留下了通过地址类型筛选结果的问题。

什么是返回所需的结果最短的方法？目前我倾向于创建一个临时表来存储中间数据。

Answer 1

最后，我决定这样的事情：

FROM (
SELECT Account.* 
FROM (SELECT Contract.Account_Id   AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Account_Id   AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Account_Id   AS ForeignKey_Id, 
       Contract.BillingAddress_Id AS Address_Id 
     FROM Contract) ContractInfo 
     JOIN Account Account 
     ON Account.Name_Id = ForeignKey_Id 
     JOIN Address 
     ON Address.Address_Id = ContractInfo.Address_Id 
      AND Address.PostalCode = 'ABCDE' 
UNION 
SELECT Account.* 
FROM (SELECT Contract.Responsible_Id  AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Responsible_Id  AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Responsible_Id  AS ForeignKey_Id, 
       Contract.BillingAddress_Id AS Address_Id 
     FROM Contract) ContractInfo 
     JOIN Account Account 
     ON Account.Name_Id = ForeignKey_Id 
     JOIN Address 
     ON Address.Address_Id = ContractInfo.Address_Id 
      AND Address.PostalCode = 'ABCDE' 
UNION 
SELECT Account.* 
FROM (SELECT Contract.Holding_Id  AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Holding_Id  AS ForeignKey_Id, 
       Contract.DeliveryAddress_Id AS Address_Id 
     FROM Contract 
     UNION 
     SELECT Contract.Holding_Id AS ForeignKey_Id, 
       Contract.BillingAddress_Id AS Address_Id 
     FROM Contract) ContractInfo 
     JOIN Account Account 
     ON Account.Name_Id = ForeignKey_Id 
     JOIN Address 
     ON Address.Address_Id = ContractInfo.Address_Id 
      AND Address.PostalCode = 'ABCDE' 
) Account 

它的性能比采用每行子查询或IN子句更好。

Answer 2

SELECT * 
FROM contract 
WHERE EXISTS 
     (
     SELECT NULL 
     FROM account 
     JOIN address 
     ON  address_id IN (billingaddress_id, deliveryaddress_id) 
     WHERE account_id IN (account_id, responsible_id, holding_id) 
       AND postalcode = @mycode 
     ) 

要选择帐户，使用此：

SELECT * 
FROM account ao 
WHERE EXISTS 
     (
     SELECT NULL 
     FROM (
       SELECT account_id, responsible_id, holding_id 
       FROM contract c 
       WHERE c.account_id = ao.account_id 
       UNION ALL 
       SELECT account_id, responsible_id, holding_id 
       FROM contract c 
       WHERE c.responsible_id = ao.account_id 
       UNION ALL 
       SELECT account_id, responsible_id, holding_id 
       FROM contract c 
       WHERE c.holding_id = ao.account_id 
       ) co 
     JOIN account ai 
     ON  ai.account_id IN (co.account_id, co.responsible_id, co.holding_id) 
     JOIN address 
     ON  address_id IN (billingaddress_id, deliveryaddress_id) 
     WHERE postalcode = @mycode 
     ) 

更新：

既然你列没有索引，EXISTS不会在这种情况下，有效的，因为它不是重写为一个IN。

你应该重写所有的加盟条件是等值连接，使HASH JOIN方法是可用的。

试试这个：

SELECT a.account_id 
FROM (
     SELECT account_id 
     FROM contract 
     UNION 
     SELECT responsible_id 
     FROM contract 
     UNION 
     SELECT holding_id 
     FROM contract 
     ) c 
JOIN (
     SELECT account_id, billingaddress_id AS address_id 
     FROM account 
     UNION 
     SELECT account_id, deliveryaddress_id 
     FROM account 
     ) a 
ON  a.account_id = c.account_id 
JOIN address ad 
ON  ad.address_id = a.address_id 
WHERE ad.postalcode = @mycode