![]() The command above should run in any Linux, Windows, or MacOS distribution that has an instance of Docker installed. NOTE: You will need Docker installed for these commands to work. To install and test PostgreSQL, I recommend using Docker:ĭocker run -name dev-postgres -p 5432:5432 -e POSTGRES_PASSWORD =mysecretpassword -d postgres:11ĭocker exec dev-postgres psql -U postgres -c "CREATE DATABASE coursedb" postgres You will need PostgreSQL installed to complete the tutorial. ![]() Why is that? Postgres means Post Ingres or the successor of Ingres, an older database that paved the way to the more famous Microsoft SQL Server and other products. Technically speaking it is also one of the most advanced relational database systems available. ![]() PostgreSQL is one of the most famous RDBMS around. A critical characteristic of RDBMS is the support for ACID transactions (Atomicity, Consistency, Isolation, Durability) which guarantee data consistency even in a concurrent environment without the developer needing to be fully aware. Initially proposed in the 70s, the RDBMS (Relational Database Management System) has grown in popularity through the years as computing processing power and storage capacity has increased. Let’s dig in! Get Started with PostgreSQL via Docker To finish, you will learn how to use PostgreSQL JSONB data structure and use PostgreSQL as a NoSQL database. Next, I’ll show you how to create SQL files to deliver database changes, which are more suitable for enterprise applications. After that, you’ll create a simple database schema and add some data to it. You will learn how to install a simple PostgreSQL instance using Docker and how to connect a Spring Boot application to it. Add whatever condition is needed, to restrict the name change to rows that are linked to a specific row in the parent table.In this tutorial, you are going to learn more about PostgreSQL and how to integrate it with a Spring Boot application. The condition tablica1_id = 1 is just an example. Then the update becomes as simple as: update names Insert into names (id, tablica1_id, firstname, lastname) Insert into test_tablica1 (id) values (1) Tablica1_id int not null references test_tablica1, Id int primary key generated always as identity, Something like: create table test_tablica1 It would be more efficient to store the names in a proper relational table with a one-to-many relationship to the base table ( test_tablica1 in your example) However, your model really looks like a mis-use of JSON in the database. The WHERE clause prevents updating rows that don't need updating The CASE expression will then check each element an if it contains the firstname Maria, the lastname will be replaced (appending a JSONB value to a JSONB value, replaces the existing keys) Jsonb_agg() aggregates the elements that are returned by jsonb_array_elements() back into an array. As podaci contains an array, you need to include the array position, e.g. The second parameter for that function requires a "target path". I don't think this can be done using jsonb_set(). If you have any suggestions on how this sort of thing should be done, I'd be more than happy to get some constructive feedback. I'd be grateful if someone could clarify what I'm doing wrong. I used dbfiddle to test out if what I am doing would work before putting anything into the real database as to not make any unnecessary mistakes. ![]() In this case I wanted to update a single element of an array by swapping out one of the 'lastName' values for another using the UPDATE command (the syntax I'm using is probably wrong but that's the most I could work out from what I've read in the official documentation). I want to change a single element of a nested array using the UPDATE, DELETE or INSERT commands. I already asked this question on stackoverflow but I didn't get a conclusive answer so I thought it might be a good idea to ask the same question here since this site is focused solely on databases and their ins and outs. First of all I'd like to say that I don't have much experience but I started learning dbs after having a couple of subjects related to dbs at my university (so please keep that in mind while you're reading this).
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