What is the use of nonce value in blockchain

1.

blockchain is a term in the field of information technology. In essence, it is a shared database. The data or information stored in it is characterized by "unforgeability", "trace in the whole process", "traceability", "openness and transparency" and "collective maintenance". Based on these characteristics, blockchain technology has laid a solid "trust" foundation, created a reliable "cooperation" mechanism, and has broad application prospects

on January 10, 2019, the state Internet Information Office issued the regulations on the management of blockchain information services. In October 24, 2019, ring the eighteenth collective learning of the Central Political Bureau, general secretary Xi Jinping stressed that "block chain as an important breakthrough in core technology and independent innovation", "accelerating the development of block chain technology and instrial innovation". "Blockchain" has entered the public field of vision and become the focus of social attention

on December 2, 2019, the word was selected into the top ten catchwords of "biting words" in 2019

extended data:

Application of blockchain Finance:

since 2016, the major financial giants have also carried out blockchain innovation projects to explore the possibility of applying blockchain Technology in various financial scenarios. In particular, Puyin group took the lead in creating a "blockchain +" standard digital currency

standard digital currency refers to the process of assets identification, evaluation, right confirmation and insurance completed by a third party organization, which is written into the blockchain through careful digital algorithm to form the standard corresponding relationship between assets and digital currency, which is called standard digital currency

in order to realize the great leap forward development of blockchain finance, promote the new development of China's economy, accelerate the circulation of global assets, and realize the dream of rejuvenation that has been struggling for generations, Puyin group will hold the Guiyang strategic development ceremony of Puyin blockchain finance in Guizhou on December 9, 2016

the meeting will discuss the realization of digital circulation of assets by blockchain, the financial transaction mode of blockchain, and the application of blockchain services and social public instry. This conference will mark the beginning of the application of blockchain finance and the change and development of the new financial ecology

2. It's a public list of all the transactions that have been sent. It ensures that everyone knows the real owner (address) of each bitcoin. All full function nodes on the network will keep a of the blockchain< Br > block is an independent unit in the blockchain. Each block contains the hash value of the previous block (so it is impossible for someone to delete or modify any block on the blockchain without making some hash values on the blockchain mismatched), as well as as as many unconfirmed transactions that can be found on the network, and a number called nonce random number. Someone who is creating a block must find a suitable nonce random number so that the hash value of the block is lower than a certain threshold (the target value). This can only be done by trying all the random numbers one after another until a random number with the desired hash value is found. The lower the target value is, the more difficult it is to find a suitable random number. Deliberately making block creation so difficult is to prevent someone from spending bitcoin, and then create and promote his own blockchain that does not include the transaction that shows that bitcoin has been spent just now, erase the transaction record once and allow him to spend bitcoin twice. When a valid block is created, it will be distributed to the whole network, and then search for the next block based on this block.

3. The solutions are as follows:
1. Regularly clean the st in the computer, turn off the computer, open the chassis, use a hair dryer and blow with cold air< At ordinary times, 360 guard, Jinshan guard and other tools should be used to clean up the system garbage and temporary files generated by the Internet, and check and kill malicious

Italian software
3. The computer configuration is poor, so try to set the virtual memory as large as possible, and install anti-virus software with less resources, such as NOD32, or only one

auxiliary anti-virus software
4. Try to set the IP to static IP, which can rece the startup time of the computer
5. Don't put too many files and icons on the computer desktop, which will slow down the reaction of the computer. Try not to install the software on disk C
6. Regularly defragment the disk. Open the drive of my computer to defragment - properties - tools

select the disk to be defragmented. Open the "disk defragmenter" window - Analysis - defragmentation - the system will start to defragment

.

4. n. (noun)
current
temporary
current
current [mainly used for the nonce]
current
paedophile or sex offender
random number (arbitrary or non repetitive value, which is included in data exchange through an agreement, Usually for the purpose of ensuring activity and thus detecting and protecting it from repeated attacks)
adj. (adjective)
temporary
once occurring
only at that time< br />" for the nonce"
Yes, please remember to adopt it! thank you

5. Nonce
English [n & 594; [n] beauty [n] ɑ [ns]
n.
at present, at present<

her sadness to discover a touch of sadness had for the nonce disappeared.
the light sadness she used to have is now swept away.

2.
this would dissolve a vocabulary into an infinite number of nonce words.
this will break a vocabulary into countless temporary words />
3.
Bob is a fool, to be dozing at the very nonce

6. Only if the field type is text type can all the query lines be added to the array:
. Version 2
. Local variable AA, integer type
. Local variable BB, text type, & quot; 0"
. Local variable field value 1, text type
. Local variable field value 2, text type
external database 1. Open the MDB database (take the running directory () + "& # 92; ZJ. MDB ",", ")
AA = external database 1. Query (" select * from ZJ where number = 1 ")
external database 1. To the first record (AA)
. Judge the loop first (external database 1. After the last record (AA) = false)
& #; Suppose table ZJ has only two fields
field value 1 = external database 1. Read (AA, 1)
field value 2 = external database 1. Read (AA, 2)
join member (BB, field value 1)
join member (BB, field value 2)
external database 1. To the next record (AA)
. Judge the end of the loop ()
external database 1. Close recordset (AA)

7.

As for this question, I suggest you go to lobby the community to have a look (web link), where there are big guys and big V to answer for you. Here I share with you an article by Mr. Ruan Yifeng, which should be able to answer your questions

I. what is the essence of blockchain? In a word, it is a special distributed database

the current rule is that new nodes always use the longest blockchain. If there is a fork in the blockchain, we will see which branch is behind the fork point and reach six new blocks first (called & quot; Six confirmations. According to the calculation of a block in 10 minutes, it can be confirmed in one hour

since the generation speed of new blocks is determined by computing power, this rule means that the branch with most computing power is the authentic blockchain

9. As an unmanaged distributed database, blockchain has been running for 8 years since 2009, and there is no big problem. This proves that it is feasible

However, in order to ensure the reliability of data, blockchain has its own costs. One is efficiency. When data is written to the blockchain, it takes at least ten minutes. If all nodes synchronize data, it takes more time; The second is energy consumption. The generation of blocks requires countless meaningless calculations by miners, which is very energy consuming

therefore, the application scenarios of blockchain are very limited

there is no management authority trusted by all members

the data written by

does not require real-time use of

the benefits of mining can make up for its own costs

if the above conditions cannot be met, then the traditional database is a better solution

at present, the biggest application scenario (and possibly the only one) of blockchain is cryptocurrency represented by bitcoin

8. Block header consists of three groups of block metadata:
firstly, a group of data referring to the hash value of the parent block is used to connect the block with the previous block in the blockchain
the second set of metadata, namely difficulty, timestamp and nonce, is related to mining competition
the third set of metadata is Merkle tree root (a data structure used to effectively summarize all transactions in a block).

9. < a> The tag's attribute is used to specify the URL of the hyperlink target. The value of the attribute can be the relative or absolute URL of any valid document, including fragment identifier and JavaScript code fragment

here, the; javascript:;& quot;， Javascript: is a pseudo protocol, which allows us to call JavaScript functions through a link; When the click event of a tag is running, if there is a lot of content on the page and there is a scroll bar, the page will not jump, and the user experience is better.