protected String generateSingleColumnSQL(AddColumnStatement statement, Database database) {
    DatabaseDataType columnType =
        DataTypeFactory.getInstance()
            .fromDescription(
                statement.getColumnType()
                    + (statement.isAutoIncrement() ? "{autoIncrement:true}" : ""),
                database)
            .toDatabaseDataType(database);

    String alterTable =
        " ADD "
            + database.escapeColumnName(
                statement.getCatalogName(),
                statement.getSchemaName(),
                statement.getTableName(),
                statement.getColumnName())
            + " "
            + columnType;

    if (statement.isAutoIncrement() && database.supportsAutoIncrement()) {
      AutoIncrementConstraint autoIncrementConstraint = statement.getAutoIncrementConstraint();
      alterTable +=
          " "
              + database.getAutoIncrementClause(
                  autoIncrementConstraint.getStartWith(), autoIncrementConstraint.getIncrementBy());
    }

    alterTable += getDefaultClause(statement, database);

    if (!statement.isNullable()) {
      alterTable += " NOT NULL";
    } else {
      if (database instanceof SybaseDatabase
          || database instanceof SybaseASADatabase
          || database instanceof MySQLDatabase
          || (database instanceof MSSQLDatabase
              && columnType.toString().equalsIgnoreCase("timestamp"))) {
        alterTable += " NULL";
      }
    }

    if (statement.isPrimaryKey()) {
      alterTable += " PRIMARY KEY";
    }

    if (database instanceof MySQLDatabase && statement.getRemarks() != null) {
      alterTable += " COMMENT '" + statement.getRemarks() + "' ";
    }

    if (statement.getAddAfterColumn() != null && !statement.getAddAfterColumn().isEmpty()) {
      alterTable += " AFTER `" + statement.getAddAfterColumn() + "` ";
    }

    return alterTable;
  }
  @Override
  public Sql[] generateSql(
      CreateTempTableStatementVertica statement,
      Database database,
      SqlGeneratorChain sqlGeneratorChain) {
    StringBuilder sql = new StringBuilder();

    sql.append("CREATE ");
    if (statement.getIsGlobal() != null) sql.append(" GLOBAL ");
    else sql.append(" LOCAL ");
    sql.append(" TEMPORARY TABLE ");
    if (statement.getSchemaName() != null) sql.append(statement.getSchemaName()).append(".");
    else sql.append(database.getDefaultSchemaName()).append(".");
    if (statement.getTableName() != null) {
      sql.append(statement.getTableName()).append(" ");
    }

    boolean isSinglePrimaryKeyColumn =
        statement.getPrimaryKeyConstraint() != null
            && statement.getPrimaryKeyConstraint().getColumns().size() == 1;

    boolean isPrimaryKeyAutoIncrement = false;

    sql.append("( ");
    Iterator<String> columnIterator = statement.getColumns().iterator();
    List<String> primaryKeyColumns = new LinkedList<String>();
    while (columnIterator.hasNext()) {
      String column = columnIterator.next();
      DatabaseDataType columnType =
          statement.getColumnTypes().get(column).toDatabaseDataType(database);
      sql.append(
          database.escapeColumnName(
              statement.getCatalogName(),
              statement.getSchemaName(),
              statement.getTableName(),
              column));

      // This is the difference between vertica & other RDBMS - the encoding part.

      AutoIncrementConstraint autoIncrementConstraint = null;

      for (AutoIncrementConstraint currentAutoIncrementConstraint :
          statement.getAutoIncrementConstraints()) {
        if (column.equals(currentAutoIncrementConstraint.getColumnName())) {
          autoIncrementConstraint = currentAutoIncrementConstraint;
          break;
        }
      }

      boolean isAutoIncrementColumn = autoIncrementConstraint != null;
      boolean isPrimaryKeyColumn =
          statement.getPrimaryKeyConstraint() != null
              && statement.getPrimaryKeyConstraint().getColumns().contains(column);
      isPrimaryKeyAutoIncrement =
          isPrimaryKeyAutoIncrement || isPrimaryKeyColumn && isAutoIncrementColumn;

      if (isPrimaryKeyColumn) {
        primaryKeyColumns.add(column);
      }
      if (!isAutoIncrementColumn) {
        sql.append(" ").append(columnType);
      }

      // for the serial data type in postgres, there should be no default value
      if (!columnType.isAutoIncrement() && statement.getDefaultValue(column) != null) {
        Object defaultValue = statement.getDefaultValue(column);
        sql.append(" DEFAULT ");
        sql.append(statement.getColumnTypes().get(column).objectToSql(defaultValue, database));
      }

      // TODO: Change this - vertica supports both auto incremental & identity fields.
      if (isAutoIncrementColumn) {
        // TODO: check if database supports auto increment on non primary key column
        if (database.supportsAutoIncrement()) {
          String autoIncrementClause =
              database.getAutoIncrementClause(
                  autoIncrementConstraint.getStartWith(), autoIncrementConstraint.getIncrementBy());

          if (!"".equals(autoIncrementClause)) {
            sql.append(" ").append(autoIncrementClause);
          }

          if (database instanceof PostgresDatabase
              && autoIncrementConstraint.getStartWith() != null) {
            String sequenceName = statement.getTableName() + "_" + column + "_seq";
            //                        additionalSql.add(new UnparsedSql("alter sequence
            // "+database.escapeSequenceName(statement.getCatalogName(), statement.getSchemaName(),
            // sequenceName)+" start with "+autoIncrementConstraint.getStartWith(), new
            // Sequence().setName(sequenceName).setSchema(statement.getCatalogName(),
            // statement.getSchemaName())));
          }
        } else {
          LogFactory.getLogger()
              .warning(
                  database.getShortName()
                      + " does not support autoincrement columns as request for "
                      + (database.escapeTableName(
                          statement.getCatalogName(),
                          statement.getSchemaName(),
                          statement.getTableName())));
        }
      }

      if (isPrimaryKeyColumn) {

        String pkName =
            StringUtils.trimToNull(statement.getPrimaryKeyConstraint().getConstraintName());
        if (pkName != null) {
          sql.append(" CONSTRAINT ");
          sql.append(database.escapeConstraintName(pkName));
        }

        sql.append(" PRIMARY KEY ");
      }

      if (statement.getNotNullColumns().contains(column)) {
        sql.append(" NOT NULL");
      }

      if (statement.getColumnEncoding(column) != null) {
        sql.append(" ENCODING ").append(statement.getColumnEncoding(column));
      }

      if (statement.getColumnAccessrank(column) != null)
        sql.append(" ACCESSRANK  ").append(statement.getColumnAccessrank(column));

      if (columnIterator.hasNext()) {
        sql.append(", ");
      }
    }
    sql.append(" )");
    sql.append(" ON COMMIT ");
    if (statement.getIsPreserve()) sql.append(" PRESERVE ");
    else sql.append(" DELETE");
    sql.append("  ROWS ");

    if (statement.getOrderby() != null) sql.append(" ORDER BY ").append(statement.getOrderby());

    if (statement.getSegmentation() != null) {
      Segmentation seg = statement.getSegmentation();
      if (seg.getUnsegmented() == true) {
        sql.append(" UNSEGMENTED ");
      } else {
        sql.append(" SEGMENTED BY ");

        sql.append(seg.getExpression());
      }
      if (seg.getAllNodes()) {
        sql.append(" ALL NODES ");
      } else {
        sql.append(" NODES ").append(seg.getNodes());
        if (seg.getOffset() != null) sql.append(" OFFSET ").append(seg.getOffset().toString());
      }
    }

    if (statement.getKsafe() != null) sql.append(" KSAFE ").append(statement.getKsafe());

    if (statement.getPartitionby() != null)
      sql.append(" PARTITION BY ").append(statement.getPartitionby());

    System.out.println(sql.toString());
    return new Sql[] {new UnparsedSql(sql.toString())};
  }