From: Tom Hughes <tom@compton.nu>
Date: Tue, 4 Sep 2007 16:22:03 +0000 (+0000)
Subject: Don't bother deleting points which don't exist before importing a
X-Git-Tag: live~8129
X-Git-Url: https://git.openstreetmap.org/rails.git/commitdiff_plain/4954f65061d593d3618ae6e2246151baca033921

Don't bother deleting points which don't exist before importing a
trace - this avoids locking the table in the common case where there
are no points to delete.
---

diff --git a/app/models/trace.rb b/app/models/trace.rb
index c189c035e..a2bebf1dd 100644
--- a/app/models/trace.rb
+++ b/app/models/trace.rb
@@ -175,7 +175,12 @@ class Trace < ActiveRecord::Base
       f_lon = 0
       first = true
 
-      Tracepoint.delete_all(['gpx_id = ?', self.id])
+      # If there are any existing points for this trace then delete
+      # them - we check for existing points first to avoid locking
+      # the table in the common case where there aren't any.
+      if Tracepoint.exists?(['gpx_id = ?', self.id])
+        Tracepoint.delete_all(['gpx_id = ?', self.id])
+      end
 
       gpx.points do |point|
         if first