public static Builder builder() {
        return new Builder();
    }
@Test
    void testWatermarkOnNonExistedField() {
        assertThatThrownBy(
                        () ->
                                TableSchema.builder()
                                        .field("f0", DataTypes.BIGINT())
                                        .field(
                                                "f1",
                                                DataTypes.ROW(
                                                        DataTypes.FIELD("q1", DataTypes.STRING()),
                                                        DataTypes.FIELD(
                                                                "q2", DataTypes.TIMESTAMP(3))))
                                        .watermark(
                                                "f1.q0", WATERMARK_EXPRESSION, WATERMARK_DATATYPE)
                                        .build())
                .isInstanceOf(ValidationException.class)
                .hasMessage("Rowtime attribute 'f1.q0' is not defined in schema.");
    }