Java统计年月日的数据量（使用mysql）

@GetMapping("/statistic/imAndOut")
@ApiOperation(value = " 统计出入库数量", httpMethod = HttpMethod.GET)
public List statisticImAndOut(StatisticsQO qo) {
    return baseService.statisticImAndOut(qo);
}

List statisticImAndOut(StatisticsQO qo);

@Override
public List statisticImAndOut(StatisticsQO qo) {
    // 如果没传时间类型，默认按"日"统计
    if (qo.getDateType() == null) {
        qo.setDateType(DateFormatEnum.DAY.getDateType());
    }
    // 如果没设置当前时间，按照系统当前时间开始计算
	if (qo.getCurrentTime() == null) {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            qo.setCurrentTime(sdf.format(new Date()));
        }
    }
    Integer step = qo.getStep();
    // 如如果展示时间没设置，默认查询7条
    if (step == null) {
        step = 7;
    }
    // 获取"当前时间"，即执行计算时间
    final LocalDateTime now = cn.hutool.core.date.DateUtil.parseLocalDateTime(qo.getCurrentTime());
    LocalDateTime start;
    final DateFormatEnum dateType = DateFormatEnum.getByDateType(qo.getDateType());
    switch (dateType) {
        case MONTH:
            start = now.minusMonths(step - 1);
            break;
        case YEAR:
            start = now.minusYears(step - 1);
            break;
        default:
            start = now.minusDays(step - 1);
    }
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
    String beginDate = start.format(formatter);
    String endDate = now.format(formatter);
    qo.setStartDate(beginDate).setEndDate(endDate)
            .setDateFormat(DateFormatEnum.getFormatByDateType(qo.getDateType()));
    return baseMapper.statisticImAndOut(qo);
}

List statisticImAndOut(@Param("qo")StatisticsQO qo);

    SELECT
    date.cdate date,IFNULL(IM.imNum,0) imNum,IFNULL(EX.exNum,0) exNum
    FROM (
        SELECt
        DATE_FORMAT(@cdate := DATE_ADD( @cdate, INTERVAL + 1 ${qo.dateType} ),#{qo.dateFormat} ) cdate
        FROM
        (SELECt @cdate := DATE_ADD(#{qo.startDate}, INTERVAL - 1 ${qo.dateType} ) FROM PL_MATERIAL_INFO LIMIT #{qo.step} )
        t0
    ) date
    LEFT JOIN (
        SELECt P1.MATERIAL_ID,COUNT(P1.ID) imNum,DATE_FORMAT(P1.CREATOR_TIME,#{qo.dateFormat}) date FROM
        PL_MATERIAL_IM_INFO P1
        LEFT JOIN PL_MATERIAL_INFO M1 ON M1.MATERIAL_ID = P1.MATERIAL_ID
        
            
                AND M1.MATERIAL_TYPE = #{qo.materialType}
            
        
        GROUP BY date
    ) IM ON date.cdate = IM.date
    LEFT JOIN (
        SELECt P2.MATERIAL_ID,COUNT(P2.ID) exNum,DATE_FORMAT(P2.CREATOR_TIME,#{qo.dateFormat}) date FROM
        PL_MATERIAL_EX_INFO P2
        LEFT JOIN PL_MATERIAL_INFO M2 ON M2.MATERIAL_ID = P2.MATERIAL_ID
        
            
                AND M2.MATERIAL_TYPE = #{qo.materialType}
            
        
        GROUP BY date
    )EX ON date.cdate = EX.date
    ORDER BY date.cdate

@Data
@ApiModel(value = "入库出库实体VO")
@Accessors(chain = true)
public class ImAndExVO implements Serializable {

    @ApiModelProperty(value = "入库数量")
    private Integer imNum;

    @ApiModelProperty(value = "出库数量")
    private Integer exNum;

    @ApiModelProperty(value = "时间")
    private String date;

}

@Data
@ApiModel(value = "统计查询条件实体")
@Accessors(chain = true)
public class StatisticsQO implements Serializable {

    @ApiModelProperty(value = "日期类型", allowableValues = "YEAR,MONTH,DAY")
    private String dateType;

    @ApiModelProperty(value = "时间格式")
    private String dateFormat;

    @ApiModelProperty(value = "数据展示条数")
    private Integer step;

    @ApiModelProperty(value = "物资类型编号")
    private String materialType;

    @ApiModelProperty(value = "开始日期,格式为 2022-10-01")
    private String startDate;

    @ApiModelProperty(value = "结束日期,格式为 2022-10-01")
    private String endDate;

}

public enum DateFormatEnum {

    
    DAY("%Y-%m-%d", "DAY"),

    
    MONTH("%Y-%m", "MONTH"),

    
    YEAR("%Y", "YEAR"),

    ;

    private final String format;

    private final String dateType;

    DateFormatEnum(String format, String dateType) {
        this.format = format;
        this.dateType = dateType;
    }

    public String getFormat() {
        return format;
    }

    public String getDateType() {
        return dateType;
    }

    
    public static DateFormatEnum getByDateType(String dateType) {
        String finalDateType = dateType.trim().toUpperCase();
        Optional optional = Arrays.stream(DateFormatEnum.values())
                .filter(item -> finalDateType.equals(item.getDateType()))
                .findFirst();
        if (!optional.isPresent()) {
            throw BusinessException.create(ErrorMessage.PARAM_WRONG, "无效的参数：" + dateType);
        }
        return optional.get();
    }

    
    public static String getFormatByDateType(String dateType) {
        String finalDateType = dateType.trim().toUpperCase();
        Optional optional = Arrays.stream(DateFormatEnum.values())
                .filter(item -> finalDateType.equals(item.getDateType()))
                .findFirst();
        if (!optional.isPresent()) {
            throw BusinessException.create(ErrorMessage.PARAM_WRONG, "无效的参数：" + dateType);
        }
        return optional.get().getFormat();
    }

}

SELECT
DATE_FORMAT(@cdate := DATE_ADD( @cdate, INTERVAL + 1 DAY ),'%Y-%m-%d' ) cdate
FROM
(SELECt @cdate := DATE_ADD('2022-05-17', INTERVAL - 1 DAY ) FROM PL_MATERIAL_INFO LIMIT 7 ) t0

1、这里的’2022-05-17’是统计开始时间。
例如，需要查2022-05-29之前12天的数据，这里在上面的serviceImpl中进行了逻辑运算，可以得到最开始的时间是2022-05-17，所以统计开始时间就是2022-05-17。
2、这里的“7”，表示查询的时间节点数是7个。
3、PL_MATERIAL_INFO这是我的项目中用到的数据表，替换为你需要统计的表即可。
注意：如果这张表里的数据量小于要查询的时间节点数，即这里的“7”，那么查询出来的时间节点数只有当前表中的数据量。