Add support for WHERE ... IN (...)

README.md

@@ -32,8 +32,8 @@ Generate SQL and parameters that can be used in **query** and **execute** expres
 (select * :person)
 ;;=> ("SELECT * FROM person")
 (select [:id :name] :person
-  (where {:email "user@domain.com"}))
-;;=> ("SELECT id,name FROM person WHERE email = ?" "user@domain.com")
+  (where {:email "user@domain.com" :sex ["M", "F"]}))
+;;=> ("SELECT id,name FROM person WHERE email = ? AND sex IN (?, ?)" "user@domain.com" "M", "F")
 (select [{:p.id :userid} :p.name :a.city] {:person :p}
   (join {:address :a} {:p.id :a.personid})
   (where {:p.email "user@domain.com"}))

src/java_jdbc/sql.clj

@@ -303,6 +303,8 @@ and update! high-level operations within clojure.java.jdbc directly." }
            " AND "
            (map (fn [k v]
                   (str (as-str entities k)
-                       (if (nil? v) " IS NULL" " = ?")))
+                       (if (sequential? v)
+                         (str " IN (" (str/join ", " (repeat (count v) "?")) ")")
+                         (if (nil? v) " IS NULL" " = ?"))))
                 ks vs))
-          (remove nil? vs))))
+          (remove nil? (flatten vs)))))

test/java_jdbc/sql_test.clj

@@ -47,7 +47,9 @@
 
 (deftest where-dsl
   (is (= ["id = ?" 42] (where {:id 42})))
-  (is (= ["id IS NULL"] (where {:id nil}))))
+  (is (= ["id IS NULL"] (where {:id nil})))
+  (is (= ["id IN (?, ?, ?, ?, ?, ?)" 4 8 15 16 23 42] (where {:id [4 8 15 16 23 42]})))
+  (is (= ["name = ? AND code IS NULL AND id IN (?, ?, ?)" "wow" 4 8 15] (where {:code nil :id [4 8 15] :name "wow"}))))
 
 (deftest select-where-dsl
   (is (#{["SELECT * FROM a WHERE c = ? AND b = ?" 3 2]