private static String generateAbstractCreateTable(List<Column> columns) {
        StringBuilder sb = new StringBuilder();
        sb.append("(\n");
        for (int i = 0; i < columns.size(); i++) {
            Column col = columns.get(i);
            sb.append("   col").append(i + 1).append(" ").append(col.type);
            if (i < columns.size() - 1) {
                sb.append(",\n");
            } else {
                sb.append("\n");
            }
        }
        sb.append(") Engine = MergeTree ORDER BY ();");
        return sb.toString();
    }
Formatter for the DateTime type with nanoseconds.
performance/src/main/java/com/clickhouse/benchmark/data/DataSetGenerator.java