Question

我正在尝试应用CTE和递归查询。该数据库是MariaDB 10.2或更高版本。

业务规则如下：

帐户可以是持股或投资组合。
控股包含一定金额。
馆藏可以是活跃的和不活跃的。
投资组合包含零个或多个帐户，这些帐户可以属于多个投资组合。
在确定投资组合的价值时，每个帐户的总价值乘以“权重”因素。

我的架构如下（注意char仅用于id类型，但我确实会使用int）：

CREATE TABLE IF NOT EXISTS accounts (
  id CHAR(4) NOT NULL,
  name VARCHAR(45) NOT NULL,
  type ENUM('holding', 'portfolio') NULL,
  PRIMARY KEY (id))
ENGINE = InnoDB;

CREATE TABLE IF NOT EXISTS holdings (
  accounts_id CHAR(4) NOT NULL,
  value DECIMAL(6,2) NOT NULL,
  active TINYINT NOT NULL,
  PRIMARY KEY (accounts_id),
  CONSTRAINT fk_holdings_accounts
    FOREIGN KEY (accounts_id)
    REFERENCES accounts (id)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB;

CREATE TABLE IF NOT EXISTS portfolios (
  accounts_id CHAR(4) NOT NULL,
  PRIMARY KEY (accounts_id),
  CONSTRAINT fk_portfolios_accounts1
    FOREIGN KEY (accounts_id)
    REFERENCES accounts (id)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB;

CREATE TABLE IF NOT EXISTS portfolios_has_accounts (
  portfolios_id CHAR(4) NOT NULL,
  accounts_id CHAR(4) NOT NULL,
  weight DECIMAL(4,2) NOT NULL,
  PRIMARY KEY (portfolios_id, accounts_id),
  INDEX fk_portfolios_has_accounts_accounts1_idx (accounts_id ASC),
  INDEX fk_portfolios_has_accounts_portfolios1_idx (portfolios_id ASC),
  CONSTRAINT fk_portfolios_has_accounts_portfolios1
    FOREIGN KEY (portfolios_id)
    REFERENCES portfolios (accounts_id)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION,
  CONSTRAINT fk_portfolios_has_accounts_accounts1
    FOREIGN KEY (accounts_id)
    REFERENCES accounts (id)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION)
ENGINE = InnoDB;

样本数据如下：

INSERT INTO accounts(id,name,type) VALUES ('p1','portfolio1','portfolio'),('p2','portfolio2','portfolio'),('p3','portfolio3','portfolio'),('h1','holding1','holding'),('h2','holding2','holding'),('h3','holding3','holding'),('h4','holding4','holding');
INSERT INTO holdings(accounts_id,value,active) VALUES ('h1','50','1'),('h2','40','0'),('h3','70','1'),('h4','40','1');
INSERT INTO portfolios(accounts_id) VALUES ('p1'),('p2'),('p3');
INSERT INTO portfolios_has_accounts(portfolios_id,accounts_id,weight) VALUES ('p1','h1','1'),('p1','p2','0.5'),('p2','h2','2'),('p2','p3','1'),('p3','h3','2'),('p3','h4','0.5');

帐户

id  name        type
p1  portfolio1  portfolio
p2  portfolio2  portfolio
p3  portfolio3  portfolio
h1  holding1    holding
h2  holding2    holding
h3  holding3    holding
h4  holding4    holding

组合

portfolios_id
p1
p2
p3

馆藏

id value active
h1  50   1
h2  40   0
h3  70   1
h4  40   1

portfolio_has_accounts

portfolios_id   accounts_id weight
p1               h1         1
p1               p2         0.5
p2               h2         2
p2               p3         1
p3               h3         2
p3               h4         0.5

我的目标是找到：

查找仅包含有效馆藏的所有帐户。给定样本数据，它是p3，h1，h3和h4。 p2不包括在内，因为它包括无效的h2，并且不包括p1，因为它包含p2。
投资组合p1的总价值。给出样本数据，它是170：1 * 50 + 0.5 *（2 * 40 + 1 *（2 * 70 + 0.5 * 40））
持有量乘以的常数导致投资组合p1的总价值。给出样本数据，它们如下（注意1 * h1 + 1 * h2 + 1 * h3 + 0.25 * h4 = 170）

id  weight
h1  1
h2  1
h3  1
h4  .25

我该如何做到这一点？

Answer 1

请评论这些是否应以不同的方式进行，或从性能角度来看，是否有任何重大问题？

目标＃1

MariaDB [recursion]> WITH RECURSIVE t AS (
    ->     SELECT accounts_id FROM holdings WHERE active=0
    ->     UNION ALL
    ->     SELECT pha.portfolios_id
    ->     FROM portfolios_has_accounts pha
    ->     INNER JOIN t ON t.accounts_id=pha.accounts_id
    -> )
    -> SELECT a.* FROM accounts a
    -> LEFT OUTER JOIN t ON t.accounts_id=a.id
    -> WHERE t.accounts_id IS NULL;
+----+------------+-----------+
| id | name       | type      |
+----+------------+-----------+
| h1 | holding1   | holding   |
| h3 | holding3   | holding   |
| h4 | holding4   | holding   |
| p3 | portfolio3 | portfolio |
+----+------------+-----------+
4 rows in set (0.00 sec)

目标＃2

MariaDB [recursion]> WITH RECURSIVE t AS (
    -> SELECT pha.*, h.value
    -> FROM portfolios_has_accounts pha
    -> LEFT OUTER JOIN holdings h ON h.accounts_id=pha.accounts_id
    -> WHERE pha.portfolios_id="p1"
    -> UNION ALL
    -> SELECT pha.portfolios_id, pha.accounts_id, pha.weight*t.weight, h.value
    -> FROM t
    -> INNER JOIN portfolios_has_accounts pha ON pha.portfolios_id=t.accounts_id
    -> LEFT OUTER JOIN holdings h ON h.accounts_id=pha.accounts_id
    -> )
    -> SELECT SUM(weight*value) FROM t WHERE value IS NOT NULL;
+-------------------+
| SUM(weight*value) |
+-------------------+
| 170.0000          |
+-------------------+
1 row in set (0.00 sec)

目标＃3

MariaDB [recursion]> WITH RECURSIVE t AS (
    -> SELECT pha.*, h.value
    -> FROM portfolios_has_accounts pha
    -> LEFT OUTER JOIN holdings h ON h.accounts_id=pha.accounts_id
    -> WHERE pha.portfolios_id="p1"
    -> UNION ALL
    -> SELECT pha.portfolios_id, pha.accounts_id, pha.weight*t.weight, h.value
    -> FROM t
    -> INNER JOIN portfolios_has_accounts pha ON pha.portfolios_id=t.accounts_id
    -> LEFT OUTER JOIN holdings h ON h.accounts_id=pha.accounts_id
    -> )
    -> SELECT accounts_id, weight FROM t WHERE value IS NOT NULL;
+-------------+--------+
| accounts_id | weight |
+-------------+--------+
| h1          | 1.00   |
| h2          | 1.00   |
| h3          | 1.00   |
| h4          | 0.25   |
+-------------+--------+
4 rows in set (0.01 sec)

MariaDB [recursion]>

将CTE应用于递归查询

1 个答案: