Abstract Database Interface

[Robik]

On Sunday, 28 October 2012 at 00:31:49 UTC, BLM768 wrote:
> I've recently been working with Ruby's ActiveRecord as part of 
> my job, and I realized that D was powerful enough to make a 
> similar abstraction layer. I've been playing with the idea for 
> a little while, and I've put up some code at 
> https://github.com/blm768/adbi. It isn't nearly as 
> comprehensive as ActiveRecord, but it captures the basic idea 
> of representing database structures as objects/structs.
>
> Using it is something like this:
>
> module main;
>
> import std.stdio;
>
> import adbi.model;
> import adbi.sqlite3.database;
>
> struct Test {
> 	mixin Model!"test";
> 	
> 	const(char)[] name;
> 	double num;
> 	mixin reference!("test2", "test2", Test2);
> }
>
> struct Test2 {
> 	mixin Model!"test2";
> 	int value;
> }
>
> int main(string[] args) {
> 	auto db = new Sqlite3Database("test.db");
> 	auto q = db.query("SELECT * FROM test;");
> 	
> 	Test.updateSchema(db);
> 	Test2.updateSchema(db);
> 	
> 	auto range = ModelRange!Test(q);
> 	
> 	foreach(value; range) {
> 		writeln(value);
> 	}
> 	
> 	auto q2 = db.query("SELECT * FROM test, test2 WHERE test2_id = 
> test2.id");
> 	
> 	auto r2 = ModelRange!(Join!(Test, Test2))(q2);
> 	
> 	foreach(j; r2) {
> 		writeln(j);
> 	}
> 	
> 	return 0;
> }
>
> This code prints out every entry in the "test" table, then 
> prints the results of a join on the "test" and "test2" tables. 
> The calls to updateSchema() set up some static members of Test 
> and Test2; after these calls, the library does not perform any 
> operations with the column names, which should make retrieving 
> a record noticeably faster than in a system like ActiveRecord. 
> The downside is that these functions must be called every time 
> the database schema changes in a way that affects column order, 
> but that should happen very rarely, if ever, in a typical 
> application.
>
> The code is far from complete, but it's an interesting toy and 
> might actually be useful for simple applications once some of 
> the issues are ironed out.

I am working on similar project, named SQLd[1]. If you are 
interested, we can join forces and work togheder :)

IRC Nick: Robik
[1]: http://github.com/robik/SQLd