diff --git a/src/fmdb/FMDatabase.h b/src/fmdb/FMDatabase.h
index ab3b6966..e85c281f 100644
--- a/src/fmdb/FMDatabase.h
+++ b/src/fmdb/FMDatabase.h
@@ -86,7 +86,7 @@ typedef int(^FMDBExecuteStatementsCallbackBlock)(NSDictionary *resultsDictionary
     NSTimeInterval      _startBusyRetryTime;
     
     NSMutableDictionary *_cachedStatements;
-    NSMutableSet        *_openResultSets;
+    NSHashTable         *_openResultSets;
     NSMutableSet        *_openFunctions;
 
     NSDateFormatter     *_dateFormat;
diff --git a/src/fmdb/FMDatabase.m b/src/fmdb/FMDatabase.m
index 566f6b12..4bde1b0c 100644
--- a/src/fmdb/FMDatabase.m
+++ b/src/fmdb/FMDatabase.m
@@ -34,7 +34,7 @@ - (instancetype)initWithPath:(NSString*)aPath {
     
     if (self) {
         _databasePath               = [aPath copy];
-        _openResultSets             = [[NSMutableSet alloc] init];
+        _openResultSets             = [NSHashTable weakObjectsHashTable];
         _db                         = nil;
         _logsErrors                 = YES;
         _crashOnErrors              = NO;
@@ -283,23 +283,15 @@ - (BOOL)hasOpenResultSets {
 - (void)closeOpenResultSets {
     
     //Copy the set so we don't get mutation errors
-    NSSet *openSetCopy = FMDBReturnAutoreleased([_openResultSets copy]);
-    for (NSValue *rsInWrappedInATastyValueMeal in openSetCopy) {
-        FMResultSet *rs = (FMResultSet *)[rsInWrappedInATastyValueMeal pointerValue];
-        
+    NSHashTable *openSetCopy = FMDBReturnAutoreleased([_openResultSets copy]);
+    for (FMResultSet *rs in openSetCopy) {
         [rs setParentDB:nil];
         [rs close];
         
-        [_openResultSets removeObject:rsInWrappedInATastyValueMeal];
+        [_openResultSets removeObject:rs];
     }
 }
 
-- (void)resultSetDidClose:(FMResultSet *)resultSet {
-    NSValue *setValue = [NSValue valueWithNonretainedObject:resultSet];
-    
-    [_openResultSets removeObject:setValue];
-}
-
 #pragma mark Cached statements
 
 - (void)clearCachedStatements {
@@ -858,8 +850,7 @@ - (FMResultSet *)executeQuery:(NSString *)sql withArgumentsInArray:(NSArray*)arr
     rs = [FMResultSet resultSetWithStatement:statement usingParentDatabase:self];
     [rs setQuery:sql];
     
-    NSValue *openResultSet = [NSValue valueWithNonretainedObject:rs];
-    [_openResultSets addObject:openResultSet];
+    [_openResultSets addObject:rs];
     
     [statement setUseCount:[statement useCount] + 1];
     
diff --git a/src/fmdb/FMResultSet.m b/src/fmdb/FMResultSet.m
index 9d6c6e17..3073a56d 100644
--- a/src/fmdb/FMResultSet.m
+++ b/src/fmdb/FMResultSet.m
@@ -2,11 +2,6 @@
 #import "FMDatabase.h"
 #import "unistd.h"
 
-@interface FMDatabase ()
-- (void)resultSetDidClose:(FMResultSet *)resultSet;
-@end
-
-
 @implementation FMResultSet
 @synthesize query=_query;
 @synthesize statement=_statement;
@@ -47,10 +42,6 @@ - (void)close {
     [_statement reset];
     FMDBRelease(_statement);
     _statement = nil;
-    
-    // we don't need this anymore... (i think)
-    //[_parentDB setInUse:NO];
-    [_parentDB resultSetDidClose:self];
     _parentDB = nil;
 }