From ad9e709d96a4c8635f52e9ee8623fa805e628de6 Mon Sep 17 00:00:00 2001
From: Taloth Saldono <Taloth@users.noreply.github.com>
Date: Sun, 15 Nov 2020 13:16:15 +0100
Subject: [PATCH] Fixed duplicate UpdateHistory items

---
 .../146_cleanup_duplicates_updatehistory.cs   | 59 +++++++++++++++++++
 .../Update/History/UpdateHistoryRepository.cs |  4 +-
 2 files changed, 61 insertions(+), 2 deletions(-)
 create mode 100644 src/NzbDrone.Core/Datastore/Migration/146_cleanup_duplicates_updatehistory.cs

diff --git a/src/NzbDrone.Core/Datastore/Migration/146_cleanup_duplicates_updatehistory.cs b/src/NzbDrone.Core/Datastore/Migration/146_cleanup_duplicates_updatehistory.cs
new file mode 100644
index 000000000..4eeeb717f
--- /dev/null
+++ b/src/NzbDrone.Core/Datastore/Migration/146_cleanup_duplicates_updatehistory.cs
@@ -0,0 +1,59 @@
+using System.Collections.Generic;
+using System.Data;
+using System.Linq;
+using FluentMigrator;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Core.Datastore.Migration.Framework;
+
+namespace NzbDrone.Core.Datastore.Migration
+{
+    [Migration(146)]
+    public class cleanup_duplicates_updatehistory : NzbDroneMigrationBase
+    {
+        protected override void LogDbUpgrade()
+        {
+            Execute.WithConnection(CleanupUpdateHistory);
+        }
+
+        private void CleanupUpdateHistory(IDbConnection conn, IDbTransaction tran)
+        {
+            var toDelete = new List<int>();
+
+            using (var cmdQuery = conn.CreateCommand())
+            {
+                cmdQuery.Transaction = tran;
+                cmdQuery.CommandText = "SELECT Id, Version FROM UpdateHistory WHERE EventType = 2 ORDER BY Date";
+
+                var lastVersion = string.Empty;
+                using (var reader = cmdQuery.ExecuteReader())
+                {
+                    while (reader.Read())
+                    {
+                        var id = reader.GetInt32(0);
+                        var version = reader.GetString(1);
+
+                        if (lastVersion == version)
+                        {
+                            toDelete.Add(id);
+                        }
+
+                        lastVersion = version;
+                    }
+                }
+            }
+
+            if (toDelete.Any())
+            {
+                using (var cmdDelete = conn.CreateCommand())
+                {
+                    var ids = toDelete.Select(v => v.ToString()).Join(", ");
+
+                    cmdDelete.Transaction = tran;
+                    cmdDelete.CommandText = $"DELETE FROM UpdateHistory WHERE Id IN ({ids})";
+
+                    cmdDelete.ExecuteNonQuery();
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/NzbDrone.Core/Update/History/UpdateHistoryRepository.cs b/src/NzbDrone.Core/Update/History/UpdateHistoryRepository.cs
index 20ea5a239..66ae01fbd 100644
--- a/src/NzbDrone.Core/Update/History/UpdateHistoryRepository.cs
+++ b/src/NzbDrone.Core/Update/History/UpdateHistoryRepository.cs
@@ -26,7 +26,7 @@ namespace NzbDrone.Core.Update.History
         public UpdateHistory LastInstalled()
         {
             var history = Query.Where(v => v.EventType == UpdateHistoryEventType.Installed)
-                               .OrderBy(v => v.Date)
+                               .OrderByDescending(v => v.Date)
                                .Take(1)
                                .FirstOrDefault();
 
@@ -36,7 +36,7 @@ namespace NzbDrone.Core.Update.History
         public UpdateHistory PreviouslyInstalled()
         {
             var history = Query.Where(v => v.EventType == UpdateHistoryEventType.Installed)
-                               .OrderBy(v => v.Date)
+                               .OrderByDescending(v => v.Date)
                                .Skip(1)
                                .Take(1)
                                .FirstOrDefault();