private static void constraintInfosToNotNullConstraints(TableName tableName, List<ConstraintInfo> notNullInfos,
      List<SQLNotNullConstraint> notNullConstraints) {
    for (ConstraintInfo notNullInfo : notNullInfos) {
      notNullConstraints.add(new SQLNotNullConstraint(tableName.getCat(), tableName.getDb(), tableName.getTable(),
          notNullInfo.colName, notNullInfo.constraintName, notNullInfo.enable, notNullInfo.validate, notNullInfo.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