public static String constructQueryValueRemove(String table, Pair pairIndex, String column){
    String query;
    if (pairIndex.getRight() instanceof Number){
        query = "UPDATE `"+table+
                "` SET `"+column+"` = NULL" +
                "WHERE `"+table+"`.`"+pairIndex.getLeft()+"` = "+pairIndex.getRight();
    } else {
        query = "UPDATE `"+table+
                "` SET `"+column+"` = NULL" +
                "WHERE `"+table+"`.`"+pairIndex.getLeft()+"` = '"+pairIndex.getRight().toString()+"'";
    }
    return query;
}

query = "UPDATE `"+table+"`"+
        "SET `"+column+"` = NULL" +
        "WHERE `"+table+"`.`"+pairIndex.getLeft()+"` = "+pairIndex.getRight();