根据日期计算数量

Question

我有此MariaDB表，希望将其用于条形图：

CREATE TABLE `payment_transaction_daily_facts` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `date` date DEFAULT NULL,
  `year` int(11) DEFAULT NULL,
  `month` int(11) DEFAULT NULL,
  `week` int(11) DEFAULT NULL,
  `day` int(11) DEFAULT NULL,
  `volume` int(11) DEFAULT NULL,
  `count` int(11) DEFAULT NULL,
  'created_at' date DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB;

在我的示例SQL查询中，我只有一列Date。 将日期，年，月，周和日分成不同的列时，如何计算最近10天的每天交易量？

最终结果应为例如：

Date       | Amount| Number of transactions per day |
11-11-2018 | 30    | 3                              |
11-12-2018 | 230   | 13                             |

我尝试了这个：

SELECT SUM(amount) AS sum_volume, COUNT(*) AS sum_Transactions
WHERE (created_at BETWEEN '2018-11-07' AND '2018-11-08')
GROUP BY DATE(created_at)

我想使用DTO返回生成的数据：

public class DashboardDTO {

    private Date date;

    private int sum_volume;

    private int sum_Transactions;

    ... getters and setters
}

休息控制器：

@RestController
@RequestMapping("/dashboard")
public class DashboardController {

    private static final Logger LOG = LoggerFactory.getLogger(DashboardController.class);

    @Autowired
    private DashboardRepository dashboardRepository;

    @Autowired
    private PaymentTransactionsDailyFactsMapper mapper;

    @GetMapping("/volumes")
    public ResponseEntity<List<DashboardDTO>> getProcessingVolumes(@PathVariable String start_date, @PathVariable String end_date) {
        List<DashboardDTO> list = StreamSupport.stream(dashboardRepository.findPaymentTransactionsDailyFacts(start_date, end_date).spliterator(), false)
                .map(mapper::toDTO)
                .collect(Collectors.toList());
        return ResponseEntity.ok(list);
    }
}

JPA查询：

public List<PaymentTransactionsDailyFacts> findPaymentTransactionsDailyFacts(LocalDateTime start_date, LocalDateTime end_date) {

        String hql = "SELECT SUM(amount) AS sum_volume, COUNT(*) AS sum_Transactions " + 
                " WHERE (created_at BETWEEN :start_date AND :end_date )" + 
                " GROUP BY DATE(created_at)";

        TypedQuery<PaymentTransactionsDailyFacts> query = entityManager.createQuery(hql,
                PaymentTransactionsDailyFacts.class).setParameter("start_date", start_date).setParameter("end_date", end_date);
        List<PaymentTransactionsDailyFacts> data = query.getResultList();
        return data;
    }

如何正确实施查询？

当我从Angular接收start_date和end_date作为String时，应如何将其转换为LocaDateTime？

Answer 1

嗯，正如我所评论的那样，时间是数据仓库星型架构中的一个维度，我想周期也是如此。 所以，你应该有两个维度表，一个TimeDim为LOCALDATE的，和PeriodDim的时期。 然后，您应该具有包含由架构中各个维度组成的EmbeddedId的Fact 。 那么您将拥有1天的事实和10天的事实。 如果您坚持要总结事实，那么您将遇到JPA无法对复合键进行<=或>=比较的问题。 由于您只累加了10天，因此可以使用in子句选择10个键，但是同样，您应该掌握所需期间的事实。

@Entity
public class TimeDim {
    @Id
    private LocalDate localDate;


@Entity
public class PeriodDim {
    @Id 
    private Period period;

// need this too
@Converter(autoApply = true)
public class LocalDateAttributeConverter implements AttributeConverter<LocalDate, Date> {
    @Override
    public Date convertToDatabaseColumn(LocalDate locDate) {
        return (locDate == null ? null : Date.valueOf(locDate));
    }
    @Override
    public LocalDate convertToEntityAttribute(Date sqlDate) {
        return (sqlDate == null ? null : sqlDate.toLocalDate());
    }
}

@SuppressWarnings("serial")
@Embeddable
public class DimKey implements Serializable {
    private LocalDate localDate;
    private Period period;

@Entity
public class Fact {
    @EmbeddedId
    private DimKey dimKey = new DimKey();
    private long amount;

例如：

tx.begin();

TimeDim td10 = new TimeDim();
td10.setLocalDate(LocalDate.now().minusDays(5));
em.persist(td10);
TimeDim td5 = new TimeDim();
td5.setLocalDate(LocalDate.now().minusDays(10));
em.persist(td5);

PeriodDim pd5 = new PeriodDim();
pd5.setPeriod(Period.ofDays(5));
em.persist(pd5);
PeriodDim pd10 = new PeriodDim();
pd10.setPeriod(Period.ofDays(10));
em.persist(pd10);

Fact f10 = new Fact();
f10.getDimKey().setLocalDate(td10.getLocalDate());
f10.getDimKey().setPeriod(pd10.getPeriod());
f10.setAmount(100);
em.persist(f10);

Fact f51 = new Fact();
f51.getDimKey().setLocalDate(td10.getLocalDate());
f51.getDimKey().setPeriod(pd5.getPeriod());
f51.setAmount(50);
em.persist(f51);

Fact f52 = new Fact();
f52.getDimKey().setLocalDate(td5.getLocalDate());
f52.getDimKey().setPeriod(pd5.getPeriod());
f52.setAmount(50);
em.persist(f52);

tx.commit();

em.clear();
DimKey dk = new DimKey();
dk.setLocalDate(td10.getLocalDate());
dk.setPeriod(pd10.getPeriod());
Fact f = em.createQuery("select f from Fact f where f.dimKey = :dimKey", Fact.class)
        .setParameter("dimKey", dk)
        .getSingleResult();
System.out.println("From 10 day period: " + f.getAmount());

DimKey dk1 = new DimKey();
dk1.setLocalDate(td10.getLocalDate());
dk1.setPeriod(pd5.getPeriod());
DimKey dk2 = new DimKey();
dk2.setLocalDate(td5.getLocalDate());
dk2.setPeriod(pd5.getPeriod());
Long sum = em.createQuery("select sum(f.amount) from Fact f where f.dimKey in (:dimKey1 , :dimKey2)", Long.class)
        .setParameter("dimKey1", dk1)
        .setParameter("dimKey2", dk2)
        .getSingleResult();
System.out.println("From 2*5 day period: " + sum);