private static void constraintInfosToDefaultConstraints(TableName tableName, List<ConstraintInfo> defaultInfos,
      List<SQLDefaultConstraint> defaultConstraints) {
    for (ConstraintInfo defaultInfo : defaultInfos) {
      defaultConstraints.add(new SQLDefaultConstraint(tableName.getCat(), tableName.getDb(), tableName.getTable(),
          defaultInfo.colName, defaultInfo.defaultValue, defaultInfo.constraintName, defaultInfo.enable,
          defaultInfo.validate, defaultInfo.rely));
    }
  }
Process the unique constraints from the ast node and populate the SQLUniqueConstraint list.
ql/src/java/org/apache/hadoop/hive/ql/ddl/table/constraint/ConstraintsUtils.java