Ethereum: What are the keys used in the blockchain levelDB (ie what are the key:value pairs)?

I will give an article on the structure of blockchain ethereum, in particular focusing on levelb and node.js.

Blockchain Ethereum structure: Deep diving in levels

Blockchain Ethereum is a decentralized, public registers system that allows you to verify and store transactions online. To understand how it works, we must break down its basic architecture.

Blockchain structure

Blockchain Ethereum consists of several layers:

• block

  

  : The block is a set of transactions. Each transaction consists of the sender, recipient, amount and other relevant data.

• Chain : The chain is a sequence of blocks that make up the Ethereum blockchain. Each block contains a shortcut of the sixteenth representation of the previous block.

• Header : The header is a unique identifier for each block. It includes metadata, such as the time marker, the number of confirmations and many others.

Leveldb: Database Database

LeveldB, a distributed database, is used for effective storage of blockchain data. Leveldb allows quick search, saving and updates of large low delay data sets.

In Blockchain architecture, Ethereum Leveldb is used to store block headlines and other metadata. This means that you can access specific blocks according to their unique header identifier.

key pairs/values ​​

To understand how crucifices of key values ​​work in levels, let’s consider the example:

Let’s assume that we want to recover the headline of the block with the following key value pairs: Block_NUMBER,Timestamp and `Nonce '.

• Block_numberis a unique block identifier.

• Timestamp represents when the block was created (in seconds from Epoch Unix).

• Nonceis an optional value that determines how many times the block creator can send transactions before confirmed.

To access this data at the level, we would use the following key pairs:

|. Key Value

|. --- | --- |

|.Block_NUMBER1234567890(actual block number)

|.Timestamp 1643723400,000z (time marker)

|. Nonce 42 (optional value)

In levels, these data are stored as a shortcut of key couples:

`Json

{

"Block_NUMBER": "1234567890",

"Time marker": "1643723400,000z",

"Nonce": "42"

}

node.js and leveldb

To access Blockchain database directly using node.js, you can use the “leveledb” package. Here is a simplified example:

`Javascript

Const level = requires ("level");

// Create a new level of levels

Const DB = level (': memory:'); // ': Memory:' This is a special key that allows database only for memory

// put some data into the database

DB.Set ("Block_NUMBER", "1234567890", {mimestamp: 1643723400,000z, nonce: 42});

db.set ("transaction_hash", "abcdefg");

// Recover the header of a specific block with its identifier

Const Blockheader = db.get ("Block_NUMBER");

console.log (blockheader);

// update the data in levelb (optional)

db.update ("block_number", {mimestamp: 1643723401.000z, nonce: 43});

In this example, we create a new level of level and enter some data to it using the “set ()`. Then we download the headline of a specific block with its identifier and update the data if necessary.

Application

The Blockchain Ethereum structure is built at the level to get efficient storage and search. Understanding how the crucifices of key values ​​work in levelb, you can access the Ethereum Blockchain database directly using node.js. However, it should be remembered that this requires the correct creation and maintenance of the level of the level.

SYNERGY CREATIVITY NFTS