Exposed VS postgres

So is it like Exposed for Kotlin which is a typesafe Kotlin DSL for building sql queries? I’ve been looking for something like this in typescript! https://github.com/JetBrains/Exposed

object TestDatabase { private val mySQLContainer: MySQLContainer = MySQLContainer("mysql:8.0.26").apply { withDatabaseName("test-db") withUsername("test-user") withPassword("test-password") start() // Start the container } init { val config = HikariConfig().apply { jdbcUrl = mySQLContainer.jdbcUrl username = mySQLContainer.username password = mySQLContainer.password driverClassName = "com.mysql.cj.jdbc.Driver" maximumPoolSize = 10 } val dataSource = HikariDataSource(config) // This doesn't connect to the database but provides a descriptor for future use // In the main app, we would do this on system start up // https://github.com/JetBrains/Exposed/wiki/Database-and-DataSource Database.connect(dataSource) // Create the schema transaction { SchemaUtils.create(Users) } } }

Exposed SQL is pretty good.

I am using Kotlins Exposed DSL to access my postgreSQL database. I am running an SQL query which involves doing a one-to-many left join, with the first table having tens of thousands of rows and the second table having millions of rows. The database is stored locally on the machine. I would expect the returned query to be less than one thousand rows.

I understand that `referrersOn` and `referencedOn` can be used, however in the documentations StarWars example, the child table needs to have a column indicating the parent_id row it is joined to. This does not work in my case as my child table can be associated to multiple parent_ids.

I am following this wiki to learn kotlin exposed. It contains an example of 'Referencing' using Star Wars data. I would like to create a scratch and/or console file in IntelliJ which reproduces this simple example. However When I try to run the code I get errors (see below). Is there something I am missing here?

Exposed by JetBrains https://github.com/JetBrains/Exposed

Alternatively there are... hybrid solutions like Kotlin's https://github.com/JetBrains/Exposed or https://jdbi.org/ that don't quite... do all the heavy lifting for querying but allow you to sorta stitch queries together manually.

In our last episode (https://youtu.be/Uza\_dWsNMUs) we worked out how to save stock items in PostgreSQL (https://www.postgresql.org/) using the JetBrains Exposed library (https://github.com/JetBrains/Exposed). This time we refactor our existing file-based storage, extracting an interface that we can implement with files, in-memory, or with Exposed. For the database version, instead of replacing items in a table when they change, we choose to implement an append-only datastore. This keeps all the old versions of every row, using a query to select the latest versions when we want to see the current state. This has the advantage that we can rebuild the state of our system if things go wrong, and may also be faster than amending when we consider transactions. This is part 62 of an exploration of where a Test Driven Development implementation of the Gilded Rose stock control system might take us in Kotlin. You can see the whole series as a playlist https://www.youtube.com/playlist?list=PL1ssMPpyqociJNwykAOB9\_KEZVW7BW7m2 and the code on GitHub https://github.com/dmcg/gilded-rose-tdd If you like this, you’ll probably like my book Java to Kotlin, A Refactoring Guidebook (http://java-to-kotlin.dev). It's about far more than just the syntax differences between the languages - it shows how to upgrade your thinking to a more functional style. I have some free time between producing videos and working for team Gilded Rose. If you like these videos I'd like to work with you - please get in touch - [email protected]

I have used hikari and exposed to do this in the past with postgres, although other dialects are supported.

I want to use this as a chance to bring attention to a GitHub issue that I think would help reduce friction for Neon:

https://github.com/neondatabase/neon/issues/4989

If the Neon driver were to allow us to easily pass in a localhost connection, the development and test experience would be easier. Perhaps Neon could swap to something like this internally: https://github.com/porsager/postgres.

Having run a local dev environment connected to Neon and tests connected to Neon got in our way of adoption. We'd prefer to develop and run tests against a regular Postgres localhost database.

To the PMs of Neon, put yourself in the shoes of a new developer thinking of giving Neon a try. What changes will I have to make to my code and my development workflow?

I'd push you to consider using postgres, slonik or similar for database queries. With these libraries, you just write SQL, but they perform input sanitization for you. So you can safely write:

Thanks Pier! Your comment saved me some frustration here :-D

https://github.com/porsager/postgres/discussions/627#discuss...

There's a core client interface here:

- https://www.postgresql.org/docs/current/client-interfaces.ht...

On what makes it postgres.js faster, from author himself:

> it seems Postgres.js is actually faster than, not only pg, but of any driver out-there

- https://github.com/porsager/postgres/discussions/627

- https://porsager.github.io/imdbench/sql.html

When viewed as a DSL for set theory, views, CTEs, set-returning functions, et al are indeed proper first-class query abstractions.

When viewed through the lens of general purpose imperative or functional programming languages, it's easy to see how it can be seen as falling short.

I'll admit much of the tooling and driver APIs leave a lot to be desired.

Some tools do make good efforts though such as nested fragments in this driver.

https://github.com/porsager/postgres#building-queries

I don't think this should turn in to an ORM or not debate, but there are plenty of reasons, especially for the crowd that would do anything to avoid ORMs. Just try to take a peek into the multitude of "ORMs are bad" articles / discussions.

For instance - I would love to be able to use https://github.com/porsager/postgres with sqlite.

Demonstrate how easily and accidentally one can make an SQL injection with these:

https://github.com/porsager/postgres

https://github.com/gajus/slonik

They've looked at Postgres.js (https://github.com/porsager/postgres) before — wouldn't mind if they enabled those other cases in the same way.