:left-join & :right-join clauses; simplifies :join syntax

README.md

@@ -2,8 +2,6 @@
 
 Turn Clojure data structures into SQL.
 
-**Work in progress**
-
 ## Leiningen Coordinate
 
 ```clj
@@ -107,26 +105,60 @@ calls, raw SQL fragments, and named input parameters:
 Here's a big, complicated query. Note that Honey SQL makes no attempt to verify that your queries make any sense. It merely renders surface syntax.
 
 ```clj
-(-> (select :f.* :b.baz :c.quux (sql/call :now) (sql/raw "@x := 10"))
+(-> (select :f.* :b.baz :c.quux [:b.bla "bla-bla"]
+            (sql/call :now) (sql/raw "@x := 10"))
     (modifiers :distinct)
     (from [:foo :f] [:baz :b])
-    (join [[:clod :c] [:= :f.a :c.d] :left]
+    (join :draq [:= :f.b :draq.x])
-          [:draq [:= :f.b :draq.x]])
+    (left-join [:clod :c] [:= :f.a :c.d])
+    (right-join :bock [:= :bock.z :c.e])
     (where [:or
-            [:and [:= :f.a "bort"] [:not= :b.baz "gabba"]]
+             [:and [:= :f.a "bort"] [:not= :b.baz (sql/param :param1)]]
-            [:in :f.e [1 2 3]]
+             [:< 1 2 3]
+             [:in :f.e [1 (sql/param :param2) 3]]
              [:between :f.e 10 20]])
-    (group :f.a) ;note the name change
+    (group :f.a)
     (having [:< 0 :f.e])
     (order-by [:b.baz :desc] :c.quux)
     (limit 50)
-    (offset 10)
+    (offset 10))
-    sql/format)
+=> {:select [:f.* :b.baz :c.quux [:b.bla "bla-bla"]
-=> ["SELECT DISTINCT f.*, b.baz, c.quux, NOW(), @x := 10 FROM foo AS f, baz AS b LEFT JOIN clod AS c ON f.a = c.d JOIN draq ON f.b = draq.x WHERE ((f.a = ? AND b.baz <> ?) OR (f.e IN (1, 2, 3)) OR f.e BETWEEN 10 AND 20) GROUP BY f.a HAVING 0 < f.e ORDER BY b.baz DESC, c.quux LIMIT 50 OFFSET 10"
+             (sql/call :now) (sql/raw "@x := 10")]
-   "bort" "gabba"]
+    :modifiers [:distinct]
+    :from [[:foo :f] [:baz :b]]
+    :join [:draq [:= :f.b :draq.x]]
+    :left-join [[:clod :c] [:= :f.a :c.d]]
+    :right-join [:bock [:= :bock.z :c.e]]
+    :where [:or
+             [:and [:= :f.a "bort"] [:not= :b.baz (sql/param :param1)]]
+             [:< 1 2 3]
+             [:in :f.e [1 (sql/param :param2) 3]]
+             [:between :f.e 10 20]]
+    :group-by [:f.a]
+    :having [:< 0 :f.e]
+    :order-by [[:b.baz :desc] :c.quux]
+    :limit 50
+    :offset 10}
+
+(sql/format *1 {:param1 "gabba" :param2 2})
+=> ["SELECT DISTINCT f.*, b.baz, c.quux, b.bla AS \"bla-bla\", NOW(), @x := 10
+     FROM foo AS f, baz AS b
+     INNER JOIN draq ON f.b = draq.x
+     LEFT JOIN clod AS c ON f.a = c.d
+     RIGHT JOIN bock ON bock.z = c.e
+     WHERE ((f.a = ? AND b.baz <> ?)
+           OR (1 < 2 AND 2 < 3)
+           OR (f.e IN (1, ?, 3))
+           OR f.e BETWEEN 10 AND 20)
+     GROUP BY f.a
+     HAVING 0 < f.e
+     ORDER BY b.baz DESC, c.quux
+     LIMIT 50
+     OFFSET 10 "
+     "bort" "gabba" 2]
 
 ;; Printable and readable
-(= *1 (read-string (pr-str *1)))
+(= *2 (read-string (pr-str *2)))
 => true
 ```
 

src/honeysql/core.clj

@@ -34,6 +34,8 @@
       :select, :merge-select, :un-select
       :from, :merge-from
       :join, :merge-join
+      :left-join, :merge-left-join
+      :right-join, :merge-right-join
       :where, :merge-where
       :group-by, :merge-group-by
       :having, :merge-having

src/honeysql/format.clj

@@ -117,7 +117,8 @@
 
 (def clause-order
   "Determines the order that clauses will be placed within generated SQL"
-  [:select :from :join :where :group-by :having :order-by :limit :offset])
+  [:select :from :join :left-join :right-join :where :group-by :having
+   :order-by :limit :offset])
 
 (def known-clauses (set clause-order))
 
@@ -242,14 +243,23 @@
 (defmethod format-clause :where [[_ pred] _]
   (str "WHERE " (format-predicate* pred)))
 
-(defn format-join [table pred & [type]]
+(defn format-join [type table pred]
   (str (when type
          (str (string/upper-case (name type)) " "))
        "JOIN " (to-sql table)
        " ON " (format-predicate* pred)))
 
 (defmethod format-clause :join [[_ join-groups] _]
-  (space-join (map #(apply format-join %) join-groups)))
+  (space-join (map #(apply format-join :inner %)
+                   (partition 2 join-groups))))
+
+(defmethod format-clause :left-join [[_ join-groups] _]
+  (space-join (map #(apply format-join :left %)
+                   (partition 2 join-groups))))
+
+(defmethod format-clause :right-join [[_ join-groups] _]
+  (space-join (map #(apply format-join :right %)
+                   (partition 2 join-groups))))
 
 (defmethod format-clause :group-by [[_ fields] _]
   (str "GROUP BY " (comma-join (map to-sql fields))))

src/honeysql/helpers.clj

@@ -78,6 +78,18 @@
 (defhelper merge-join [m clauses]
   (update-in m [:join] concat clauses))
 
+(defhelper left-join [m clauses]
+  (assoc m :left-join clauses))
+
+(defhelper merge-left-join [m clauses]
+  (update-in m [:left-join] concat clauses))
+
+(defhelper right-join [m clauses]
+  (assoc m :right-join clauses))
+
+(defhelper merge-right-join [m clauses]
+  (update-in m [:right-join] concat clauses))
+
 (defmethod build-clause :group-by [_ m fields]
   (assoc m :group-by (collify fields)))
 

test/honeysql/core_test.clj

@@ -12,8 +12,9 @@
                ;;(un-select :c.quux)
                (modifiers :distinct)
                (from [:foo :f] [:baz :b])
-               (join [[:clod :c] [:= :f.a :c.d] :left]
+               (join :draq [:= :f.b :draq.x])
-                     [:draq [:= :f.b :draq.x]])
+               (left-join [:clod :c] [:= :f.a :c.d])
+               (right-join :bock [:= :bock.z :c.e])
                (where [:or
                        [:and [:= :f.a "bort"] [:not= :b.baz (sql/param :param1)]]
                        [:< 1 2 3]
@@ -30,8 +31,9 @@
             ;;:un-select :c.quux
             :modifiers :distinct
             :from [[:foo :f] [:baz :b]]
-            :join [[[:clod :c] [:= :f.a :c.d] :left]
+            :join [:draq [:= :f.b :draq.x]]
-                   [:draq [:= :f.b :draq.x]]]
+            :left-join [[:clod :c] [:= :f.a :c.d]]
+            :right-join [:bock [:= :bock.z :c.e]]
             :where [:or
                     [:and [:= :f.a "bort"] [:not= :b.baz (sql/param :param1)]]
                     [:< 1 2 3]
@@ -49,7 +51,7 @@
       (is (= m1 m3)))
     (testing "SQL data formats correctly"
       (is (= (sql/format m1 {:param1 "gabba" :param2 2})
-             ["SELECT DISTINCT f.*, b.baz, c.quux, b.bla AS \"bla-bla\", NOW(), @x := 10 FROM foo AS f, baz AS b LEFT JOIN clod AS c ON f.a = c.d JOIN draq ON f.b = draq.x WHERE ((f.a = ? AND b.baz <> ?) OR (1 < 2 AND 2 < 3) OR (f.e IN (1, ?, 3)) OR f.e BETWEEN 10 AND 20) GROUP BY f.a HAVING 0 < f.e ORDER BY b.baz DESC, c.quux LIMIT 50 OFFSET 10 "
+             ["SELECT DISTINCT f.*, b.baz, c.quux, b.bla AS \"bla-bla\", NOW(), @x := 10 FROM foo AS f, baz AS b INNER JOIN draq ON f.b = draq.x LEFT JOIN clod AS c ON f.a = c.d RIGHT JOIN bock ON bock.z = c.e WHERE ((f.a = ? AND b.baz <> ?) OR (1 < 2 AND 2 < 3) OR (f.e IN (1, ?, 3)) OR f.e BETWEEN 10 AND 20) GROUP BY f.a HAVING 0 < f.e ORDER BY b.baz DESC, c.quux LIMIT 50 OFFSET 10 "
               "bort" "gabba" 2])))
     (testing "SQL data prints and reads correctly"
       (is (= m1 (read-string (pr-str m1)))))))