-1

如何优化此查询

WITH stats AS (SELECT a.IntegratorSalesAssociateID,
                      a.AgentName,
                      (
                          SELECT COUNT(*)
                          FROM properties AS p
                          WHERE a.IntegratorSalesAssociateID = p.IntegratorSalesAssociateID
                            AND p.TransactionType = '2'
                            AND MONTH(p.OrigListingDate) = MONTH(CURRENT_DATE)
                            AND YEAR(p.OrigListingDate) = YEAR(CURRENT_DATE)
                      ) AS properties_this_month
               FROM agents AS a)
SELECT stats.*,
       DENSE_RANK() over (ORDER BY stats.properties_this_month DESC) AS 'rank'
from stats

我想也许如果我加入这两个表并以某种方式对它们进行分组,它会执行得更好,目前它运行 17.5 秒,奇怪的是,添加dense_rank 根本不会影响性能。

相关表结构

CREATE TABLE `agents`
(
    `IntegratorSalesAssociateID` varchar(15) COLLATE utf8mb4_unicode_ci NOT NULL,
    `AgentName`                  varchar(100) COLLATE utf8mb4_unicode_ci     DEFAULT NULL,
    `created_at`                 timestamp                              NULL DEFAULT NULL,
    `updated_at`                 timestamp                              NULL DEFAULT NULL
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;


CREATE TABLE `properties`
(
    `id`                         bigint(20) UNSIGNED                    NOT NULL,
    `IntegratorSalesAssociateID` varchar(13) COLLATE utf8mb4_unicode_ci NOT NULL,
    `TransactionType`            tinyint(4)                             NOT NULL,
    `OrigListingDate`            date                                        DEFAULT NULL,
    `created_at`                 timestamp                              NULL DEFAULT NULL,
    `updated_at`                 timestamp                              NULL DEFAULT NULL
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

4

2 回答 2

0

你可以试试这个:

;WITH stats AS
(
    SELECT 
       p.IntegratorSalesAssociateID
       , COUNT(*) AS properties_this_month
    FROM properties AS p
    WHERE p.TransactionType = '2'
        AND MONTH(p.OrigListingDate) = MONTH(CURRENT_DATE)
        AND YEAR(p.OrigListingDate) = YEAR(CURRENT_DATE)
    GROUP BY p.IntegratorSalesAssociateID
)
SELECT 
   a.IntegratorSalesAssociateID
   , a.AgentName
   , COALESCE(s.properties_this_month, 0) AS properties_this_month
FROM agents AS a
LEFT JOIN stats s ON a.IntegratorSalesAssociateID = s.IntegratorSalesAssociateID
于 2021-02-09T09:18:34.433 回答
0

鉴于DENSE_RANK()不影响性能,您要优化:

SELECT a.IntegratorSalesAssociateID,
       a.AgentName,
       (SELECT COUNT(*)
        FROM properties p
        WHERE a.IntegratorSalesAssociateID = p.IntegratorSalesAssociateID AND
              p.TransactionType = '2' AND
              MONTH(p.OrigListingDate) = MONTH(CURRENT_DATE) AND
              YEAR(p.OrigListingDate) = YEAR(CURRENT_DATE)
         ) AS properties_this_month
FROM agents a;

我会将其重写为:

SELECT a.IntegratorSalesAssociateID,
       a.AgentName,
       (SELECT COUNT(*)
        FROM properties p
        WHERE a.IntegratorSalesAssociateID = p.IntegratorSalesAssociateID AND
              p.TransactionType = 2 AND
              p.OrigListingDate >= CURRENT_DATE - INTERVAL (1 - DAY(CURRENT_DATE) DAY
         ) AS properties_this_month
FROM agents a;

这两个变化是:

  • TransactionType看起来像一个数字。假设是,我删除了单引号。不要混合数据类型!当然,如果列是字符串,则使用单引号。
  • 我更改了日期逻辑以删除列上的所有功能。我假设没有未来的“原始”日期。如果是这样,您可以在月底添加另一个条件。

然后,对于这个查询,您需要一个索引: properties(IntegratorSalesAssociateID, TransactionType, OrigListingDate)。实际上,该索引可能适用于数据的原始版本。

我真诚地怀疑使用显式聚合会提高性能。 GROUP BY-- 尽管相当强大 -- 通常比相关子查询慢。并且使用正确的索引几乎总是更慢(或至少不是更快)。

于 2021-02-09T12:51:59.740 回答