From 6cb47b91b34871133947b1b97075067a1ddc1a13 Mon Sep 17 00:00:00 2001
From: Jack Christensen <jack@jackchristensen.com>
Date: Fri, 14 Jul 2017 08:57:25 -0500
Subject: [PATCH] Use insert on conflict for url shortener example

fixes #290
---
 examples/url_shortener/main.go | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/examples/url_shortener/main.go b/examples/url_shortener/main.go
index f6a22c37..695a5be6 100644
--- a/examples/url_shortener/main.go
+++ b/examples/url_shortener/main.go
@@ -26,19 +26,9 @@ func afterConnect(conn *pgx.Conn) (err error) {
 		return
 	}
 
-	// There technically is a small race condition in doing an upsert with a CTE
-	// where one of two simultaneous requests to the shortened URL would fail
-	// with a unique index violation. As the point of this demo is pgx usage and
-	// not how to perfectly upsert in PostgreSQL it is deemed acceptable.
 	_, err = conn.Prepare("putUrl", `
-    with upsert as (
-      update shortened_urls
-      set url=$2
-      where id=$1
-      returning *
-    )
-    insert into shortened_urls(id, url)
-    select $1, $2 where not exists(select 1 from upsert)
+    insert into shortened_urls(id, url) values ($1, $2)
+    on conflict (id) do update set url=excluded.url
   `)
 	return
 }