How to connect to PostgreSQL database using pgAdmin 4?

 How to connect to PostgreSQL database using pgAdmin 4? In order to set up a connection to the PostgreSQL database, run pgAdmin 4, for example, from the Start menu. As a result, pgAdmin 4 will start. Then click the menu "Object->Create->Server" or right-click on the item "Servers" and select "Create->Server". The server connection settings window will open. On the General tab, we invent and enter the name of our server in the Name field. On the Connection tab, enter the server IP address, username, password, and if you want, you can check the “Save password?” to save the password and not to enter it every time you connect. If the standard port (5432) of the PostgreSQL server has been changed, then you also need to change it here. Press the "Save" button. Note! The PostgreSQL server must be installed, configured and running. We considered an example of installing and configuring PostgreSQL DBMS on Linux Debian in the material “Installing ...

Relationship between algorithm and cryptocurrency space

 Relationship between algorithm and cryptocurrency space


In the very first virtual currency, PoW is needed to achieve consensus in the network. Since at any given time for each user there can be several versions of the blockchain at once, the algorithm determines which one is reliable. To implement his idea, Nakamoto took advantage of the developments of the Hashcash project mentioned above, slightly modifying the finished function (adding a mechanism for changing its complexity, which depends on the total computing power of all network nodes). The finished function is called SHA-256.



The PoW algorithm is necessary for checking by network nodes that the miner has performed calculations. The latter performs calculations of complex algorithms, as a result of which a new generated block (“cell”) is added to the block chain, storing a certain number of records of completed transactions. The proof-of-work mechanism attempts to find the hash of the node header, which contains a reference to the previous "cell" and the total value of all operations placed in the newly generated node. Hash exponents correspond to the set degree.