Postgres and other database interfaces

[Joe]

Back on 13 January, I posted in the Learn forum some questions 
regarding using Postgres and got a reply that stated the 
following:

On Monday, 15 January 2018 at 02:28:29 UTC, Matthias Klumpp wrote:
> In any case, please don't start another Postgres library and 
> consider contributing to one of the existing ones, so that we 
> maybe have one really awesome, 100% complete library at some 
> point.

I'm revisiting this because I now have had the chance to look at 
the various libraries and IMHO the "really awesome, 100% complete 
library" depends on the users' goals and their definition of 
awesome and complete.

Aside from ddbc which is like ODBC/JDBC and thus supports 
multiple db's (not my interest), I've found five 
Postgres-specific libraries worthy of further exploration:

1. derelict-pq. This is the most downloaded one and is simply a 
binding over libpq, so AFAICT it's nearly 100% complete. It's 
also well-documented, in part because the Derelict libraries 
provide overall guidance, but mainly because a D user can refer 
directly to the comprehensive libpq documentation and (C) 
examples. The only strange fact is that it's been stuck in a 
beta.3 release for the last five months.

2. dpq2. Second most downloaded and built on top of derelict-pq. 
The "documentation" consists of a README listing the features and 
a single example, which appears to focus on support for JSON/BSON.

3. vibe-d-postgresql. Third most downloaded and built on top of 
dpq2. Docs consist of a single example program.

4. ddb. About the same number of downloads as the above. 
Implemented on top of front/backend protocol. No documentation 
although repository has a folder with two sample programs.

5. dpq. Implements its own wrapper over libpq and has some ORM 
functionality. Docs are a README with example program.

The main issue is that, other than derelict-pq, using any of 
these libraries involves reading the library code and 
understanding the sui generis interfaces implemented by each.

I'm new to the D community, but coming from Python, the contrast 
is significant. First there is the well-documented PEP 249 
(https://www.python.org/dev/peps/pep-0249/) promulgated by the 
Python DB-SIG (and note that 249 is v.2), which led to the 
implementation of psycopg (also well-documented including various 
extensions to the API) and many other adapters to Postgres and 
other databases.

Since I'm new, I don't know if there's any interest in moving in 
such a direction.