mysql - sql statement optimization issues

{Code...} Assuming that the amount of data in table c is millions, how to optimize these two pieces of data to make the execution faster. Thank you

女神的闺蜜爱上我 2017-06-14 10:50:39 0  4  1063

mysql optimization - How to optimize mysql count(id) query speed?

The table structure is shown in the figure. The current data volume is 8000W rows. Are there any optimization methods and ideas?

某草草 2017-05-18 10:51:05 0  7  978

php website speed optimization

PHP website speed optimization, URL: http://www.daitianxiapr.com/esf; if any master is willing to join the fire, please add me on WeChat 13880287714

代天下房产置业顾问黄先生 2021-07-27 18:06:26 0  1  1136

javascript - requirejs module optimization problem

When the requirejs module is optimized and packaged, a module ID will be added to the anonymous define function after it is packaged. Can it be configured to be anonymous define after packaging?

黄舟 2017-05-19 10:25:19 0  1  670

javascript - performance optimization issues

How to optimize this code? The boss said that it should be converted into ES6 map data structure. I may have done it wrong and it seems to be slower. This is the optimization I did. It seems to be slower. Please give me some advice.

高洛峰 2017-07-05 10:54:21 0  6  1047

Optimization of Mongodb index?

It is not clear that there is no optimization in the index village. There is no in-depth understanding of indexes. Please help explain it by the way! 1. Each piece of data has geographical information. (province, city), then I created the index: {code...} My doubt is, when this was created, there wa...

伊谢尔伦 2017-05-17 10:01:49 0  2  707

javascript - View of tail call optimization

After reading Ruan Yifeng's ES6 tutorial, I don't know much about tail call optimization. I would like to ask how to monitor memory changes in chrome. I checked the memory in Take Heap Snapshot in Memory, but I don't know which part of the data I should focus on. The code is as shown in the figure:

过去多啦不再A梦 2017-05-19 10:07:08 0  1  592

javascript - For an editor like tinyMCE, it is definitely inappropriate for me to directly put its source code into the project for version control. Is there any automation solution?

For an editor like tinyMCE, it is definitely inappropriate for me to directly put its source code into the project for version control. Is there any automation solution?

伊谢尔伦 2017-06-21 10:11:17 0  2  928

javascript - optimization of a regular expression

Match the integer of 1024-65535, that is, 65535 >= x >= 1024. Use regular expressions to write it. Mine is /^(102[4-9]|10[3-9]d{1}|1[ 1-9]d{2}|[2-9]d{3}|[1-5]d{4}|6[0-4]d{3}|65[0-4]d{2} |655[0-2]d{1}|6553[0-5])$/ Is there a more concise and optimized way to write it?

伊谢尔伦 2017-05-19 10:09:54 0  4  598

javascript - Front-end performance optimization, how to locate the blank time between timeLine resources?

I just came into contact with the front-end optimization of a project. When I looked at timeLine in Google Developer Tools, I found that there was a blank space between two resources, as shown in the picture. I don’t know what caused it. How to locate & optimize it? .]

世界只因有你 2017-06-26 10:51:10 0  2  867

Optimization of roles and display of passwords during editing

Why not just use {$vo.gid>1?'Developer':'System Administrator'} when optimizing roles? Isn't this more straightforward? I want to display the password of the edit button. After adding value="{$data.item.password}", the username and password fields in the add button should be empty, but ...

自渡 2018-10-09 14:42:34 0  0  1269

Problems with Python3.6 int optimization mechanism, 64-bit machines (-5 to 257)

Optimization mechanism in Python (both 2.7 and 3.5): Numbers between -5~257, if you use the first assignment method, they still belong to the same memory. But the test code I wrote on my local machine is as follows: As a result, this does not comply with the above. Then I compiled it on the Python o...

ringa_lee 2017-05-18 10:54:54 0  1  799

In mysql optimization, the field setting is not null.

In mysql optimization, try to avoid setting fields to null, which will affect query speed. This refers to whether only the index field is not set to null, or it is best not to set all fields to null.

Craile 2020-04-05 10:27:28 0  3  1399

javascript - The data in Vue is obtained through Ajax, and then Vue is instantiated. How to control the Ajax request to be executed first after the page is loaded, and then instantiate Vue after the request is successful?

The data in Vue is obtained through Ajax, and then Vue is instantiated. How to control the Ajax request to be executed first after the page is loaded, and then instantiate Vue after the request is successful?

曾经蜡笔没有小新 2017-06-26 10:50:56 0  7  936

javascript - Two jQuery operations trigger the same function, how to optimize the writing?

{Code...} For example, if you click a button or press Enter in the input box to perform the same operation, can it be optimized into the following type of code: {Code...}

phpcn_u1582 2017-05-19 10:34:29 0  1  445

Optimizing React Application Performance: An Efficient Way to Render Large Numbers of Projects

I'm developing a React application and need to display a large list of items (thousands of rows). Currently, performance is very slow when the user scrolls through the list or filters items. Is there any way to optimize the performance of my React application to improve user experience? Some additio...

P粉733166744 2024-01-16 20:43:20 0  1  462

mysql optimization gender optimization

There are hundreds of thousands of users in the database, 90% of whom are men. Sex = 1. For example: select uid member where sex =1 and xxx xx. Then the sex table will be scanned. How to deal with this?

怪我咯 2017-05-18 10:51:08 0  3  767

php - A website running online, how to check whether which sql statement needs optimization?

For example, if a website is running online and it is found that a certain page loads slowly, how can you check whether a SQL statement needs to be optimized?

天蓬老师 2017-06-05 11:07:52 0  5  691

Mongodb optimization?

The current scenario is: the performance of the machine is that the CPU is very nb. I forgot the model number of i7. nb means that there are very few CPU operations during querying. View it through htop. But the memory is not good, it is only 8g, and the memory will definitely be increased in the fu...

黄舟 2017-05-17 10:02:32 0  2  847

Under what circumstances should cache be used? How to optimize the front and back ends (mini program page)

A product details interface, query data through product ID, and the front end mainly displays a picture. Database field pictue: the saved picture address, the picture is stored on the server. The problem now is that the pictures are loading too slowly, sometimes it takes a second to open, and someti...

小萝卜头 2020-05-16 18:32:29 0  3  1370