diff --git a/src/NzbDrone.Core.Test/Datastore/Migration/079_dedupe_tagsFixture.cs b/src/NzbDrone.Core.Test/Datastore/Migration/079_dedupe_tagsFixture.cs
index 47ac33b8a..6ce90cdc3 100644
--- a/src/NzbDrone.Core.Test/Datastore/Migration/079_dedupe_tagsFixture.cs
+++ b/src/NzbDrone.Core.Test/Datastore/Migration/079_dedupe_tagsFixture.cs
@@ -144,5 +144,60 @@ namespace NzbDrone.Core.Test.Datastore.Migration
 
             Mocker.Resolve<SeriesRepository>().Get(1).Tags.First().Should().Be(1);
         }
+
+        [Test]
+        public void should_only_update_affected_series()
+        {
+            WithTestDb(c =>
+            {
+                c.Insert.IntoTable("Series").Row(new
+                {
+                    Tvdbid = 1,
+                    TvRageId = 1,
+                    Title = "Title1",
+                    CleanTitle = "CleanTitle1",
+                    Status = 1,
+                    Images = "",
+                    Path = "c:\\test",
+                    Monitored = 1,
+                    SeasonFolder = 1,
+                    Runtime = 0,
+                    SeriesType = 0,
+                    UseSceneNumbering = 0,
+                    LastInfoSync = "2000-01-01 00:00:00",
+                    Tags = "[2]"
+                });
+
+                c.Insert.IntoTable("Series").Row(new
+                {
+                    Tvdbid = 2,
+                    TvRageId = 2,
+                    Title = "Title2",
+                    CleanTitle = "CleanTitle2",
+                    Status = 1,
+                    Images = "",
+                    Path = "c:\\test",
+                    Monitored = 1,
+                    SeasonFolder = 1,
+                    Runtime = 0,
+                    SeriesType = 0,
+                    UseSceneNumbering = 0,
+                    LastInfoSync = "2000-01-01 00:00:00",
+                    Tags = "[]"
+                });
+
+                c.Insert.IntoTable("Tags").Row(new
+                {
+                    Label = "test"
+                });
+
+                c.Insert.IntoTable("Tags").Row(new
+                {
+                    Label = "test"
+                });
+            });
+
+            Mocker.Resolve<SeriesRepository>().Get(2).Tags.Should().BeEmpty();
+        }
     }
 }
diff --git a/src/NzbDrone.Core/Datastore/Migration/079_dedupe_tags.cs b/src/NzbDrone.Core/Datastore/Migration/079_dedupe_tags.cs
index e990a0bc7..800b10d99 100644
--- a/src/NzbDrone.Core/Datastore/Migration/079_dedupe_tags.cs
+++ b/src/NzbDrone.Core/Datastore/Migration/079_dedupe_tags.cs
@@ -116,8 +116,9 @@ namespace NzbDrone.Core.Datastore.Migration
                 using (IDbCommand updateCmd = conn.CreateCommand())
                 {
                     updateCmd.Transaction = tran;
-                    updateCmd.CommandText = String.Format(@"UPDATE {0} SET Tags = ?", table);
+                    updateCmd.CommandText = String.Format(@"UPDATE {0} SET Tags = ? WHERE Id = ?", table);
                     updateCmd.AddParameter(model.Tags.ToJson());
+                    updateCmd.AddParameter(model.Id);
 
                     updateCmd.ExecuteNonQuery();
                 }