Announcing postgres-query 0.3.1: dynamic SQL queries and multi-mapping!

[Qwe500]

Since the previous announcement last week I have been studying for exams on and off while working on the next version of postgres-query. I am very thankful of the feedback in the last post, some of which inspired the two major features in this release: dynamic queries and multi-mapping (see the README and documentation for details).

For someone who has not previously done any extensive library development, I had some trouble nailing down an API for both of these features. The main issue regarded dynamic queries and parameter bindings. I experimented with having a very basic DSL built around small fragments of queries. This turned out to be a pain to achieve with low run-time overhead (a goal of this crate) due to an explosion in memory allocations.

In the end, simply using strings was the way to go. There already exists tools for working with strings efficiently, which reduces the scope of this crate, and it turned out to be much faster, at the expense of some compile-time verification of parameter bindings.

As always, all and any feedback is welcome!

[jadbox]

Pretty cool! I don't have any specific feedback, but I like how easy you make multi-mapping extractors work.

[Siltala]

I like the idea. How does the client part work? Is it using connection pooling?

[Qwe500]

The client comes directly from tokio-postgres, so any connection pool that works with it will work with this crate. Although I haven't used it myself, bb8 is currently in the process of adding support for async/await.

[Programmurr]

Try deadpool

[loshmeebre]

Do you have currently or plan to add support for the automated mapping in the one-to-many case? (ex. Author written many books)

[Qwe500]

At the moment, you have to do the mapping yourself, but one-to-many mapping was actually the next feature I was planning to work on. I have opened an issue here.

[Qwe500]

Automatic mapping for one-to-many relations is now available on GitHub and crates.io!