Example code

Below you will find illustrative examples. In addition we recommend viewing the screencast which accompanied the beta1 release of ClojureQL found here - The content is dated but still relevant, with only two exceptions: to-sql is now renamed to compile and with-results has an updated syntax which you can see under documentation.

Select all

user=> (table :users)
SELECT users.* FROM users

The simplest of all queries. When reading, disregard the user=> part as it simply demonstrates that these queries are executed in a REPL.

Select certain columns

user=> (-> (table :users)
           (project [:id :name :email]))
SELECT users.id,users.name,users.email FROM users

Project is a non-additive way to specify which columns to include in the select.

Sort the results

user=> (-> (table :users)
           (sort [:id]))
SELECT users.* FROM users ORDER BY id asc

If you do not specify sorting order (asc / desc) then asc is assumed.

Sort in descending order

user=> (-> (table :users)    
           (sort [:id#desc]))
SELECT users.* FROM users ORDER BY users.id desc

Multiple calls to sort

user=> (-> (table :users)
           (sort [:id#asc])
           (sort [:id#desc]))
SELECT * FROM (SELECT users.* FROM users ORDER BY users.id asc) ORDER
BY users.id desc

sort, take and limit spawn subselect when called multiple times on the same table.

Limit / Offset

user=> (-> (table :users)         
           (take 5)
           (drop 2))
SELECT users.* FROM users LIMIT 3 OFFSET 2

Distinct

user=> (-> (table :users) distinct)
SELECT DISTINCT users.* FROM users

Distinct is mostly interesting because of its simple implementation, demonstrating how simple it is for users to extend ClojureQL. Here is a sample implementation:

(defn distinct
  "A distinct which works on both tables and collections"
  [table]
  (modify obj :distinct))

Aggregates

user=> (-> (table :users) 
           (aggregate [[:count/* :as :cnt]] [:id]))
SELECT users.id,count(*) AS cnt FROM users GROUP BY users.id

Aggregates accepts an optional second argument which is a vector containing the column names to group by. Above you also see the syntax for aliasing.