# clojure-sql

A DSL for [Clojure][1] to compose queries using the constructs of
[Relational Algebra][2]. The RA constructs are then compiled into an
SQL query to be run on a DBMS. `clojure-sql` doesn't connect to a
database itself, but rather can be configured to perform an action
when a query is dereferenced.

`clojure-sql` provides some utility functions beyond strict RA to
allow for data to be inserted, updated and deleted.

`clojure-sql` provides no mechanism to create database schemas.

[1]: http://clojure.org/
[2]: http://en.wikipedia.org/wiki/Relational_Algebra

## Database support

`clojure-sql` aims to have an extensible compiler. Compilation of
queries is performed by multimethods which dispatch on an arbitrary
(and otherwise unused) `db` parameter. This allows the compilation of
queries to be entirely special-cased per database. By default
`clojure-sql` will produce SQL for PostgreSQL.

## Usage

    (require '[clojure-sql.core :as s])

    (-> (s/table :users)
        (s/project [:id :username]))
    ; => ["SELECT \"users\".\"id\", \"users\".\"username\" FROM \"users\""]

    (-> (s/table {:users :u})
        (s/project [:id :username])
        (s/rename {:id :uid})
        (s/join (-> (s/table {:people :p})
                    (s/project {:id :pid, :fname :first})
                    (s/select '(= :first "Henry")))
                '(= :uid :pid))
        (s/project [:username]))
    ; => ["SELECT \"u\".\"username\" FROM \"users\" AS \"u\" JOIN \"people\" AS \"p\" ON (\"u\".\"id\" = \"p\".\"id\") WHERE (\"p\".\"fname\" = ?)" "Henry")]

    (require '[clojure-sql.jdbc :as jdbc])
    ; => nil 
    (jdbc/use-jdbc! "postgres://user:pass@localhost:5432/db")
    ; => nil


## License

Copyright © 2013 FIXME

Distributed under the Eclipse Public License, the same as Clojure.