sum（否則結束的情況）語句

Question

我有一個可以運行的SQL Server SQL語句，但是它看起來很雜亂且效率低下。 它檢查每一行數據以獲取其數據，並將其分組為Yesterday ， WeektoDate ， MonthtoDate和YeartoDate ， MonthtoDate組對每個字段求和。 有一個更好的方法嗎？

以下是我所擁有的示例，實際查詢中實際上有15個左右的字段，這使SELECT查詢很長，是否有更好的方法呢？

SELECT
    sum(CASE when row_date BETWEEN @YesterdayMorning and @EndOfYesterday THEN Total_Calls ELSE 0 END) AS Calls_Yesterday
   ,sum(CASE when row_date BETWEEN @YesterdayMorning AND @EndOfYesterday THEN Total_Time ELSE 0 END) AS Time_Yesterday
   ,sum(CASE when row_date BETWEEN @WTDMorning and @EndOfYesterday THEN Total_Calls ELSE 0 END) AS Calls_WTD
   ,sum(CASE when row_date BETWEEN @WTDMorning AND @EndOfYesterday THEN Total_Time ELSE 0 END) AS Time_WTD
   ,sum(CASE when row_date BETWEEN @MTDMorning and @EndOfYesterday THEN Total_Calls ELSE 0 END) AS Calls_MTD
   ,sum(CASE when row_date BETWEEN @MTDMorning AND @EndOfYesterday THEN Total_Time ELSE 0 END) AS Time_MTD
   ,sum(CASE when row_date BETWEEN @YTDMorning and @EndOfYesterday THEN Total_Calls ELSE 0 END) AS Calls_YTD
   ,sum(CASE when row_date BETWEEN @YTDMorning AND @EndOfYesterday THEN Total_Time ELSE 0 END) AS Time_YTD
FROM TableName

Answer 1

一種選擇是擺脫CASE ，將它們分解為具有WHERE條件的多個SELECT查詢，然后將它們合並：

SELECT
    'Yesterday' AS Range
    SUM(Total_Calls) AS Calls,
    SUM(Total_Time) AS Time
FROM TableName
WHERE row_date BETWEEN @YesterdayMorning AND @EndOfYesterday
UNION
SELECT
    'WTD' AS Range,
    SUM(Total_Calls) AS Calls,
    SUM(Total_Time) AS Time
FROM TableName
WHERE row_date BETWEEN @WTDMorning AND @EndOfYesterday
UNION
SELECT
    'MTD' AS Range,
    SUM(Total_Calls) AS Calls,
    SUM(Total_Time) AS Time
FROM TableName
WHERE row_date BETWEEN @MTDMorning AND @EndOfYesterday
UNION
SELECT
    'YTD' AS Range,
    SUM(Total_Calls) AS Calls,
    SUM(Total_Time) AS Time
FROM TableName
WHERE row_date BETWEEN @YTDMorning AND @EndOfYesterday

Answer 2

我認為您的查詢效率不高，查詢計划看起來還可以，但是我同意代碼有點混亂。 我會考慮這樣的事情，以避免重復的代碼：

• 將所有早晨日期添加到表中
• 將日期加入通話表
• 通話總和和通話時間

查詢：

DECLARE @day VARCHAR(2) = FORMAT(DAY(GETDATE()), '00'), @month VARCHAR(2) = FORMAT(MONTH(GETDATE()), '00'), @year INT = YEAR(GETDATE());
DECLARE @weekday INT = DATEPART(dw, GETDATE());
DECLARE @morningTime TIME = '08:00';
DECLARE @EndOfYesterday DATETIME2 = DATEADD(dd, -1, CONVERT(DATETIME2, CONCAT(YEAR(GETDATE()), MONTH(GETDATE()), DAY(GETDATE()), ' 18:00')));

DECLARE @timeTable TABLE(ID INT IDENTITY(1,1) PRIMARY KEY, Name VARCHAR(255), FromDate DATETIME2);

INSERT INTO @timeTable
SELECT 'Yesterday', DATEADD(dd, -1, CONVERT(DATETIME2, CONCAT(@year, @month, @day, ' ', @morningTime)))
UNION ALL SELECT 'WTDMorning', DATEADD(dd, -(@weekday-1), CONVERT(DATETIME2, CONCAT(@year, @month, @day, ' ', @morningTime)))
UNION ALL SELECT 'MTDMorning', CONVERT(DATETIME2, CONCAT(@year, @month, '01', ' ', @morningTime))
UNION ALL SELECT 'YTDMorning', CONVERT(DATETIME2, CONCAT(@year, '01', '01', ' ', @morningTime))

SELECT t.Name, Total_Calls = SUM(c.Total_Calls), Total_Time = SUM(c.Total_Time) 
FROM @timeTable t
LEFT JOIN TableName c ON c.row_date BETWEEN t.FromDate AND @EndOfYesterday
GROUP BY ID, t.Name
ORDER BY ID

在我的測試數據上，您的查詢實際上比我的查詢低15％的查詢成本，但是在“調用表”上有索引時，我的查詢比您的查詢便宜20％。

指數：

CREATE NONCLUSTERED INDEX idxRowDate
ON [dbo].[TableName] ([row_date])
INCLUDE ([Total_Calls],[Total_Time])

我知道這與您的輸出100％不匹配，但是我相信行比15+列更容易使用。 如果需要，也可以將其轉換為一行。

一排支持：

如果需要，可以使用動態sql將行轉換為一行。 但這變得更加復雜：

DECLARE @onRowconverter VARCHAR(MAX) = '';
SELECT @onRowconverter = @onRowconverter + CASE WHEN @onRowconverter > '' THEN ', ' ELSE 'SELECT ' END +  CONCAT('[Calls_' + t.Name + '] = ', SUM(c.Total_Calls),  ', [Time_' + t.Name + '] = ', SUM(c.Total_Time))
FROM @timeTable t
LEFT JOIN TableName c ON c.row_date BETWEEN t.FromDate AND @EndOfYesterday
GROUP BY ID, t.Name
ORDER BY ID

EXEC(@onRowconverter);