获取连续日期时间

在项目中，有时候需要按日期/时间统计，例如2023-06-21至2023-06-28期间每一天的数据，如果某一天没有数据，也要查询出来，用NULL处理。

1.示例

2.连续日期效果SQL

DECLARE @StartDate DATE = '2023-06-21', -- 开始时间
        @EndDate DATE = '2023-06-28';   -- 结束时间

SELECT CONVERT(NVARCHAR(10), DATEADD(DAY, number, @StartDate), 120) AS DayTime
FROM master..spt_values
WHERE type = 'p'
      AND number <= DATEDIFF(DAY, @StartDate, @EndDate);

3.连续日期效果

4.完整代码

DECLARE @StartDate DATE = '2023-06-21';
DECLARE @EndDate DATE = '2023-06-28';
DECLARE @DeviceNo NVARCHAR(20) = N'ZN-27-722';
--注意where条件的位置 DeviceNo
SELECT 
       CASE WHEN TestTime IS NULL THEN dates.Date ELSE TestTime END AS TestTime,
       DeviceNo,
       DeviceName
FROM
(
    SELECT CONVERT(NVARCHAR(10), DATEADD(DAY, number, @StartDate), 120) AS Date
    FROM master..spt_values
    WHERE type = 'p'
          AND number <= DATEDIFF(DAY, @StartDate, @EndDate)
) dates
    LEFT JOIN PreOrder ON dates.Date = CAST(TestTime AS DATE) AND DeviceNo = @DeviceNo
ORDER BY TestTime;