Cocoapods FMDB / SQLCipher 2.7.5无法解密

Question

我已经通过cocoapods将FMDB / SQLCipher（2.7.5）添加到了我的应用程序中。

use_frameworks!
pod 'FMDB/SQLCipher'

并执行以下代码：

- (void)decryptDBAtPath:(NSString *)path withKey:(NSString *)key {
   FMDatabaseQueue *queue = [FMDatabaseQueue databaseQueueWithPath:path];
   [queue inTransaction:^(FMDatabase * _Nonnull db, BOOL * _Nonnull rollback) {
      BOOL result = [db setKey:key];
      NSLog(@"decrypt db %@", result ? @"success" : @"failed");
      //it always return YES.

      NSString *sql = @"SELECT * FROM PTypeImage";
      FMResultSet *rs = [db executeQuery:sql];
      NSDictionary *dic = [rs resultDictionary];
      NSLog(@"query test with result : %@", dic);
      //query can not by executed. 'file is not a database'.
  }];
}

总是返回解密成功，但查询失败。 我的代码有任何错误吗？

我还尝试了FMDB加密。看来失败了。返回加密成功，但可以不使用密钥打开的情况。

- (void)enryptDBAtPath:(NSString *)path withKey:(NSString *)key {
  FMDatabase *db = [FMDatabase databaseWithPath:path];
  if ([db open]) {
      BOOL result = [db rekey:key];
      //always return YES.
      NSLog(@"encrypt db %@", result ? @"success" : @"failed");
      [db close];
  }
}