psql-query.patch

diff --git a/benchmarks/targets/postgres.rs b/benchmarks/targets/postgres.rs
index bb63c4e..91b583a 100644
--- a/benchmarks/targets/postgres.rs
+++ b/benchmarks/targets/postgres.rs
@@ -41,7 +41,7 @@ pub fn make(dbn: &str, getters: usize) -> Box<Backend> {
     let conn = pool.get().unwrap();
 
     // create tables
-    conn.execute("CREATE TABLE art (id bigint, title varchar(255), votes bigint)",
+    conn.execute("CREATE TABLE art (id bigint, title varchar(255))",
                  &[])
         .unwrap();
     conn.execute("CREATE TABLE vt (u bigint, id bigint)", &[]).unwrap();
@@ -65,7 +65,7 @@ impl Backend for r2d2::Pool<PCM> {
 
 impl Putter for PC {
     fn article<'a>(&'a mut self) -> Box<FnMut(i64, String) + 'a> {
-        let prep = self.prepare("INSERT INTO art (id, title, votes) VALUES ($1, $2, 0)").unwrap();
+        let prep = self.prepare("INSERT INTO art (id, title) VALUES ($1, $2)").unwrap();
         Box::new(move |id, title| {
             prep.execute(&[&id, &title]).unwrap();
         })
@@ -73,17 +73,15 @@ impl Putter for PC {
 
     fn vote<'a>(&'a mut self) -> Box<FnMut(i64, i64) + 'a> {
         let pv = self.prepare("INSERT INTO vt (u, id) VALUES ($1, $2)").unwrap();
-        let pa = self.prepare("UPDATE art SET votes = votes + 1 WHERE id = $1").unwrap();
         Box::new(move |user, id| {
             pv.execute(&[&user, &id]).unwrap();
-            pa.execute(&[&id]).unwrap();
         })
     }
 }
 
 impl Getter for PC {
     fn get<'a>(&'a self) -> Box<FnMut(i64) -> Option<(i64, String, i64)> + 'a> {
-        let prep = self.prepare("SELECT id, title, votes FROM art WHERE id = $1").unwrap();
+        let prep = self.prepare("SELECT art.id, art.title, COUNT(vt.u) FROM art LEFT JOIN vt USING (id) WHERE art.id = $1 GROUP BY art.id, art.title").unwrap();
         Box::new(move |id| {
             for row in prep.query(&[&id]).unwrap().iter() {
                 return Some((row.get(0), row.get(1), row.get(2)));