Question

我有一个MySQL数据库表，每天大约有10-15k个插入，并且肯定会在下个月增加。

- Table Example (reservations): *important fields*
+----+--------+----------+---------+-----+
| ID | people | modified | created | ... |
+----+--------+----------+---------+-----+

我需要提供每日统计信息，根据用户选择的日期或日期范围通知条目数（总数和指定人数相同）。今天我每次请求都要执行两个查询。它工作正常，有理想的延迟，但我想知道它是否会有更多数据稳定。

- Single Date:
SELECT COUNT(*) from reservations WHERE created='DATE USER SELECTED'
SELECT COUNT(*), people from reservations WHERE created='DATE USER SELECTED' GROUP BY people

- Date Range:
 SELECT COUNT(*) from reservations WHERE created BETWEEN 'DATE USE SELECTED' AND 'DATE USE SELECTED';
 SELECT COUNT(*), people from reservations WHERE created BETWEEN 'DATE USE SELECTED' AND 'DATE USE SELECTED' GROUP BY people

IN MY VIEW
Pros: Real time statistics.
Cons: Can overload the database, with similar and slow queries.

我想创建一个名为＆＃39; statistics＆＃39;的辅助表，每天早上在我的服务器上运行一个cronjob来计算所有统计信息。

 - Table Example (statistics):

+----+------+--------------------+---------------------------+---------------------------+-----+
| ID | date | numberReservations | numberReservations2People | numberReservations3People | ... |
+----+------+--------------------+---------------------------+---------------------------+-----+

- IN MY VIEW
Pros: Faster queries, do not need to count every request.
Cons: Not real time statistics.

你怎么看？这是一个更好的方法吗？

Answer 1

如果您的表中包含正确的复合索引，则可以有效地满足您显示的汇总查询。如果您不确定复合索引，可以阅读它们。

(created,people)上的索引reservations是这两个查询的正确索引。他们都可以通过一种称为松散范围扫描的高效索引扫描来满足。你会发现它们足够快，你不需要为辅助表而烦恼在您的系统中可预见的未来。

这很好，因为像你提出的二级表是混淆和错误的常见来源。

MySQL查询生成表统计信息

1 个答案: