public List<String> addExplainPlans(String sql) {
    List<String> exp = new ArrayList<String>();
    for (String ex : explain_plans) {
      exp.add(sql.replaceAll("(?i)explain ddl", ex) + ";");
    }
    return exp;
  }
Add all the constraints for the given table. Will populate the constraints list.

@param tb
ql/src/java/org/apache/hadoop/hive/ql/exec/DDLPlanUtils.java