一个sql查询相关的问题
有一个表groups,下面有很多个字段
id
user
cost
type
addtime
uptime
note
.....
type里面有5个类型,分别是001-005,
现在要的结果就是查询最近6个月,001-005的总数,
比如查询一月份,1号到31号,TYPE为001-005的数据
select count(*) from groups where type='001' and addtime= '20130130'
select count(*) from groups where type='002' and addtime= '20130230'
select count(*) from groups where type='003' and addtime= '20130330'
select count(*) from groups where type='004' and addtime= '20130430'
select count(*) from groups where type='005' and addtime= '20130530'
查询6个月的话就需要查询30次。
如果有很多人登录这个系统,查询这样的SQL很耗费时间,我试过如果同时三个人都打开这个页面,大概反应时间要3秒以上
我的思路就是有没有办法把这些查询结果写到一个表里面,这样查询的时候我直接查询的表的数据 ,然后这些SQL的数据我可以设置一个时间
自动查询结果然后更新到一个表里面。这样我直接从表里面查询数据比用 count查询来得快,但是这个应该怎么实现呢,我现在用的就是最笨的
办法,一个一个来查询,好卡啊。
回复讨论(解决方案)
select count(*) from groups where type in('001','002','003','004','005') and addtime>='20130101' and addtime
select count(*) from groups where type in('001','002','003','004','005') and addtime>='20130101' and addtime
你好,谢谢回复,这样查询出来就是一个总和,我想要单独的一个值
比如TYPE =001 一月份 总数是 20
TYPE=002 1月份 总数是500
TYPE=003 1月份 总数是3987
TYPE=004 1月份 总数是9898
TYPE=005 1月份 总数是123
select count(*) from groups where addtime>='20130101' and addtime <= '20130630' group by addtime,type
select type, left(addtime,6) as addtime, count(*) as cnt from groups group by 1, 2
那连in都不用了 group by type, DATE_FORMAT(addtime,‘m%’) 这样试一下
select count(*) from groups where addtime>='20130101' and addtime <= '20130630' group by MONTH(addtime),type
select count(*) from groups where addtime>='20130101' and addtime <= '20130630' group by substring(addtime,4,2),type
2中方式:
1、使用SQL写临时表
2、建立where条件相关的索引;
临时表是个不错的选择,数据处理完就自动释放了!
用group by+1
自己研究一下怎么写
实在不行用缓存减少查询...

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics











In PHP, password_hash and password_verify functions should be used to implement secure password hashing, and MD5 or SHA1 should not be used. 1) password_hash generates a hash containing salt values to enhance security. 2) Password_verify verify password and ensure security by comparing hash values. 3) MD5 and SHA1 are vulnerable and lack salt values, and are not suitable for modern password security.

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.

PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.

Using preprocessing statements and PDO in PHP can effectively prevent SQL injection attacks. 1) Use PDO to connect to the database and set the error mode. 2) Create preprocessing statements through the prepare method and pass data using placeholders and execute methods. 3) Process query results and ensure the security and performance of the code.
