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Comment by harperlee | Hacker News Reader

One shower idea that I had is the concept of a clojure version that instead of compiling to JVM bytecode, javascript or CLR, compiled to postgreSQL. I think that would be awesome: you could just run the same functions, seamlessly, from the database, through the web server, to the browser. And, whilst of course you need to know about the limitations of the database, it could be great for pushing code to the database seamlessly.

Unfortunately I don't think I have the skills for that, so posting here in the hopes that someone that can likes the idea :)

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This is kind of what LINQ does. You write a query in C#. The structure of the query (like an abstract syntax tree) can be exposed to the query provider which can interpret it or compile it to the CLR or compile it to SQL or whatever.

Which can lead to great, or less ideal results.. Seeing some of the resulting queries via monitoring are wild though.

At work we've got a LINQ query that gets passed around a few functions, eventually getting into a core of 60 lines of LINQ logic. Colleague verified that chaining selects produces different output, but gets ran at the same speed (Chain selects in order to somewhat declare variables, Select(x => new { x, y = <query-x> }) then you can Select(xy => new { use xy.y multplie times }))

Sometimes I think I should just be using sql.. (which we do on other projects)

Yeah, I've been pretty happy without ORM in node.js, I even wrote a semi-nice wrapper so I could turn template strings into parameterized queries. Made writing a bunch of migration scripts a cakewalk.

Sometimes it's really just easier to write SQL directly.

A sufficiently advanced LINQ (http://wiki.c2.com/?SufficientlySmartCompiler) would do wonders in some cases, but I haven't encountered it. AFAIK, LINQ to SQL only knows about joins and some aggregate functions.

One thing that makes improving it cumbersome is that the semantics of many operations are slightly different in the database than in C#. For example, SQL Server doesn't do NaNs and infinities, supports a zillion string string collations, and its date types may not 100% map to C# ones.

Also, databases may run stored procedures faster than the SQL that LINQ genrerates on the fly because they can cache their query plans (most databases will detect that an on-the-fly query is equal to one run recently, though, so this may be somewhat of a moot argument)

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