Fixing that the Fingerprint column was too big for an index

Lombiq · Apr 2, 2015 · bf20609 · bf20609
1 parent 635a188
commit bf20609
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Showing 2 changed files with 33 additions and 11 deletions.
diff --git a/Migrations.cs b/Migrations.cs
@@ -24,7 +24,7 @@ public int Create()
             SchemaBuilder.CreateTable(typeof(CombinedFileRecord).Name,
                 table => table
                     .Column<int>("Id", column => column.PrimaryKey().Identity())
-                    .Column<string>("Fingerprint", column => column.NotNull().WithLength(1024))
+                    .Column<string>("Fingerprint", column => column.NotNull().WithLength(50))
                     .Column<int>("Slice")
                     .Column<string>("Type")
                     .Column<DateTime>("LastUpdatedUtc")
@@ -36,7 +36,7 @@ public int Create()
             );
 
 
-            return 13;
+            return 14;
         }
 
         public int UpdateFrom1()
@@ -149,17 +149,14 @@ public int UpdateFrom8()
 
         public int UpdateFrom9()
         {
-            // Changing cache file folder
-            _cacheFileService.Empty();
-
+            // Cache empty call removed as it causes exception with certain versions.
 
             return 10;
         }
 
         public int UpdateFrom10()
         {
-            // Cache files are now in a hidden folder in Media
-            _cacheFileService.Empty();
+            // Cache empty call removed as it causes exception with certain versions.
 
 
             return 11;
@@ -191,6 +188,26 @@ public int UpdateFrom12()
             return 13;
         }
 
+        public int UpdateFrom13()
+        {
+            // Cannot alter a column that is part of a key or an index.
+            SchemaBuilder.AlterTable(typeof(CombinedFileRecord).Name,
+                table => table.DropIndex("FileFingerprint")
+                );
+
+            SchemaBuilder.AlterTable(typeof(CombinedFileRecord).Name,
+                table => table.AlterColumn("Fingerprint", column => column.WithType(DbType.String).WithLength(50))
+                );
+
+            SchemaBuilder.AlterTable(typeof(CombinedFileRecord).Name,
+                table => table
+                    .CreateIndex("FileFingerprint", new[] { "Fingerprint" })
+                );
+
+
+            return 14;
+        }
+
 
         public void Uninstall()
         {

diff --git a/Services/CacheFileService.cs b/Services/CacheFileService.cs
@@ -76,11 +76,11 @@ public void Save(string fingerprint, CombinatorResource resource, Uri resourceBa
                 return;
             }
 
-            var sliceCount = _fileRepository.Count(file => file.Fingerprint == fingerprint);
+            var sliceCount = _fileRepository.Count(file => file.Fingerprint == ConvertFingerprintToStorageFormat(fingerprint));
 
             var fileRecord = new CombinedFileRecord()
             {
-                Fingerprint = fingerprint,
+                Fingerprint = ConvertFingerprintToStorageFormat(fingerprint),
                 Slice = ++sliceCount,
                 Type = resource.Type,
                 LastUpdatedUtc = _clock.UtcNow,
@@ -139,7 +139,7 @@ public IList<CombinatorResource> GetCombinedResources(string fingerprint, bool u
                 _combinatorEventMonitor.MonitorCacheEmptied(cacheKey);
                 _combinatorEventMonitor.MonitorBundleChanged(cacheKey, fingerprint);
 
-                var files = _fileRepository.Fetch(file => file.Fingerprint == fingerprint).ToList();
+                var files = _fileRepository.Fetch(file => file.Fingerprint == ConvertFingerprintToStorageFormat(fingerprint)).ToList();
                 var fileCount = files.Count;
 
                 var resources = new List<CombinatorResource>(fileCount);
@@ -181,7 +181,7 @@ public bool Exists(string fingerprint, bool useResourceShare)
                 _combinatorEventMonitor.MonitorCacheEmptied(cacheKey);
                 _combinatorEventMonitor.MonitorBundleChanged(cacheKey, fingerprint);
                 // Maybe also check if the file exists?
-                return _fileRepository.Count(file => file.Fingerprint == fingerprint) != 0;
+                return _fileRepository.Count(file => file.Fingerprint == ConvertFingerprintToStorageFormat(fingerprint)) != 0;
             });
         }
 
@@ -261,5 +261,10 @@ private static string MakeCacheKey(string name)
         {
             return CachePrefix + name;
         }
+
+        private static string ConvertFingerprintToStorageFormat(string fingerprint)
+        {
+            return fingerprint.GetHashCode().ToString();
+        }
     }
 }