code: @Override
      public void deleteStoreIfPresent(String storeName) {
          DBConn dbConn = getDBConnection();
          try {
              synchronized (m_schemaLock) {
                  if (m_schemaMgr.columnFamilyExists(dbConn, m_keyspace, storeName)) {
                      m_schemaMgr.deleteColumnFamily(dbConn, storeName);
                  }
              }
          } finally {
              returnDBConnection(dbConn);
          }
      }
docs: createStoreIfAbsent