Merge pull request #837 from Thorium/clear-cache

Potential fix for #836

src/SQLProvider.DesignTime/SqlDesignTime.fs

@@ -900,6 +900,26 @@ type public SqlTypeProvider(config: TypeProviderConfig) as this =
               designTimeCommandsContainer.AddMember m
               yield mOld :> MemberInfo
 
+              let clearCacheType = ProvidedTypeDefinition("ClearConnectionCache", Some typeof<obj>, isErased=true)
+              clearCacheType.AddMember(ProvidedConstructor([], empty))
+              clearCacheType.AddMembersDelayed(fun () ->
+
+                    match con with
+                    | Some con when con.State <> ConnectionState.Closed -> con.Close()
+                    | _ -> ()
+
+                    DesignTimeCache.cache.Clear()
+                    GC.Collect()
+
+                    [ ProvidedProperty("Done",typeof<unit>, getterCode = empty) :> MemberInfo ]
+              )
+              clearCacheType.AddXmlDocComputed(fun () -> "Close possible design-time database connection and clear connection cache")
+              let clearC = ProvidedProperty("ClearConnection", (clearCacheType :> Type), getterCode = empty)
+              clearC.AddXmlDocComputed(fun () -> "You can try to use this to refresh your database connection if you changed your database schema.")
+
+              designTimeCommandsContainer.AddMember clearC
+              serviceType.AddMember clearCacheType
+
               serviceType.AddMember designTimeCommandsContainer
               yield designTime :> MemberInfo