diff --git a/lib/db/keyer.go b/lib/db/keyer.go
index b8f9b523..e40377e3 100644
--- a/lib/db/keyer.go
+++ b/lib/db/keyer.go
@@ -21,19 +21,44 @@ const (
 )
 
 const (
-	KeyTypeDevice          = 0
-	KeyTypeGlobal          = 1
-	KeyTypeBlock           = 2
+	// KeyTypeDevice <int32 folder ID> <int32 device ID> <file name> = FileInfo
+	KeyTypeDevice = 0
+
+	// KeyTypeGlobal <int32 folder ID> <file name> = VersionList
+	KeyTypeGlobal = 1
+
+	// KeyTypeBlock <int32 folder ID> <32 bytes hash> <§file name> = int32 (block index)
+	KeyTypeBlock = 2
+
+	// KeyTypeDeviceStatistic <device ID as string> <some string> = some value
 	KeyTypeDeviceStatistic = 3
+
+	// KeyTypeFolderStatistic <folder ID as string> <some string> = some value
 	KeyTypeFolderStatistic = 4
-	KeyTypeVirtualMtime    = 5
-	KeyTypeFolderIdx       = 6
-	KeyTypeDeviceIdx       = 7
-	KeyTypeIndexID         = 8
-	KeyTypeFolderMeta      = 9
-	KeyTypeMiscData        = 10
-	KeyTypeSequence        = 11
-	KeyTypeNeed            = 12
+
+	// KeyTypeVirtualMtime <int32 folder ID> <file name> = dbMtime
+	KeyTypeVirtualMtime = 5
+
+	// KeyTypeFolderIdx <int32 id> = string value
+	KeyTypeFolderIdx = 6
+
+	// KeyTypeDeviceIdx <int32 id> = string value
+	KeyTypeDeviceIdx = 7
+
+	// KeyTypeIndexID <int32 device ID> <int32 folder ID> = protocol.IndexID
+	KeyTypeIndexID = 8
+
+	// KeyTypeFolderMeta <int32 folder ID> = CountsSet
+	KeyTypeFolderMeta = 9
+
+	// KeyTypeMiscData <some string> = some value
+	KeyTypeMiscData = 10
+
+	// KeyTypeSequence <int32 folder ID> <int64 sequence number> = KeyTypeDevice key
+	KeyTypeSequence = 11
+
+	// KeyTypeNeed <int32 folder ID> <file name> = <nothing>
+	KeyTypeNeed = 12
 )
 
 type keyer interface {