Read and write separation

How to configure environment variables to realize the read-write separation function of the database?

思远 2020-05-29 22:20:32 0  0  1220

java - Write lock degradation problem in read-write lock

When the write lock is downgraded, the thread that has currently acquired the write lock is required to hold the write lock, then acquire the read lock, and then release the write lock. So why is it required to hold the write lock? ? In the above picture, it is mentioned that "then the current ...

大家讲道理 2017-06-12 09:24:17 0  3  1227

file - Python how to read the file content and write it back to the original file after modification

How Python reads the file content and writes it back to the original file after modification

给我你的怀抱 2017-06-28 09:25:30 0  1  1139

mysql_replication - What to do if a single writing database cannot meet the performance requirements when mysql reads and writes are separated?

When mysql reads and writes are separated, what should I do if a single writing database cannot meet the performance? Should I use multiple databases to write? So how to synchronize data and ensure data consistency?

学习ing 2017-06-20 10:05:42 0  2  944

mysql - Why does database read-write separation improve database performance?

Please see the blog above for why read-write separation can improve database performance. According to database common sense, read-write separation can indeed improve database performance, but you don't know if you understand its underlying principles. For example, one reads and one writes, but the ...

PHPz 2017-05-24 11:34:46 0  2  1330

Will Linux report an error when using mv to move files that are being read and written?

1) What will happen if you use the mv command to remove the file being read in the Linux system? For example, file 1.txt is being read by process A. If I use the mv command to move 1.txt to another directory, will process A make an error? 2) What will happen if mv removes the file being written? For...

世界只因有你 2017-05-18 10:51:33 0  2  1877

"Attempting to read while the reader is closed has no effect."

I'm trying to write data from mysqluinlgc# to a .txt file but I'm getting the error "Invalid read attempt while reader is closed.". The code is here: StreamWritersr_Produto=newStreamWriter(@"C:\Enzo\PAP\PAP\Ficheiros\produto.txt",true);bdcon.Open();MySqlCommandcmd=newMySqlCommand...

P粉884667022 2024-03-31 14:58:58 0  1  415

How to write multi-select box into database

For example, if I want to write the above code into the database, and then the database reads out the hobbies I choose. how to write

别。 2019-09-11 15:08:04 0  1  1064

javascript - js reads a value in one of the excel columns as 0.3556 but reads 0.35559999999999997?

A value in one of the excel columns read by js is 0.3556, but the read value is 0.35559999999999997. But if you delete 0.3556 manually and write it manually, it will be fine. Why is this?

PHP中文网 2017-07-05 11:01:05 0  3  1137

PHP object-oriented cannot read mariadb

PHP is written in an object-oriented way, why can't the data be read in the select with where (>ω<). &nbs

仰望星空 2020-06-05 15:20:11 0  1  1098

javascript - Problems with reading data in vuejs

As shown in the picture, I used Vuejs to write a small demo for posting, but now I can only read the img field in the post. How to read all the fields? html code js code

扔个三星炸死你 2017-06-24 09:43:38 0  2  852

Firebase React Hook Error: Cannot read property of undefined (reading '_repo')

I'm writing a hook to get the userole from the live database in next js and I'm getting the error "Cannot read property of undefined (reading '_repo')". This is what my hook looks like import{useEffect,useState}from"react";import{useRouter}from"next/router";import{onAut...

P粉436688931 2024-03-20 12:15:03 0  1  428

html5 - How does FileReader read multiple files at once?

{Code...} As above, for an input that supports multiple image uploads, how to use filereader to read the dataurl of each image locally? How to write this upload?

曾经蜡笔没有小新 2017-06-07 09:24:35 0  1  801

javascript - js plugin reads local files

I want to write a jq plug-in that allows the user to select a local file and then read the file. How can I select the file and then read it directly or get the absolute path? Both are acceptable. However, after searching for a long time, I found that the absolute path problem is difficult to obtain ...

PHP中文网 2017-06-12 09:33:01 0  4  1196

ios - Why do some books say that the initialization method and dealloc method should always read and write data through instance variables?

Effective objecttive -c2.0 This book says that in the initialization method and dealloc method, you should always read and write data through instance variables. After reading it for a long time, I didn’t understand the reason? Has anyone read this book?

我想大声告诉你 2017-05-17 10:05:31 0  1  1034

Prevent MySQL from reading when updating

I have two simple queries, one to read the table and one to update the table. How to lock the read of a select query while the update query is running. Now in MySQLInnoDB, I noticed that writes/updates are locked by default, but reads/selects get the old data before the transaction. I tried using a ...

P粉190883225 2023-11-07 18:05:53 0  1  636

Problem with reading central control attendance machine data using PHP

This is a demo found on the Internet. The device connection and communication are normal. I have also tried to write data, but I cannot get the read data. After $SerialNumber is passed in, there is no change. This is the SDK definition after running.

niko 2021-09-02 12:18:06 0  3  1360

javascript - How to read files in koa

I am new to Koa. I use ctx in app.use to directly return the HTML string and it can be displayed. However, when I use fs.readFile and assign data to ctx.body in the callback, the browser displays not found. How should I write it? , not found

習慣沉默 2017-05-16 13:36:38 0  2  806

How do everyone write PHP programs to process the HTML code entered by the user?

In order to filter HTML and JS code, should htmlspecialchars() be called before writing the library or when reading the library? Or what?

PHPz 2017-05-27 17:43:23 0  2  935

Writing to a directory like Documents folder - Stack Overflow

How to write the following directory into Documents? The actual requirement is to load a website locally. I did an experiment myself. If I put it into the Documents folder and read the index.html file in it, it can be loaded normally. So I want to write the website files to the Documents file direct...

黄舟 2017-05-17 10:06:36 0  1  777